Gemological Institute of America (GIA) Graduate Diamonds Practice Exam

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• The face-up outline of a gem is known as its what?
• What makes convincing diamond simulants convincing?
• Why is it important to include design and craftsmanship in the cut grade?
• Which statement best reflects production of simulants?
• In order to conclusively identify a stone, what is needed?
• The general category for articles and data about the diamond market is best described by which term?
• Which impurity is responsible for blue color in type IIb diamonds?
• Which statement about pavilion depth percentage estimates is true for grading and appraising?
• What conditions are required for natural diamond formation?
• Which term refers to an early brilliant cut with a circular girdle?
• How does the energy level of luminescence compare to the energy of the stimulating radiation?
• What modern developments made diamond cutting more efficient and more profitable?
• Culet size can affect which pavilion dimension, potentially differing from its visual appearance?
• Which term describes any gemstone cut other than a standard round brilliant?
• How does DiamondView compare to routine fluorescence observations in terms of wavelength and energy?
• Which term describes the appearance of a material's surface in reflected light?
• Which term describes the change in speed and possible change in direction of light as it travels from one material to another?
• Which term describes the process in which the outer surface of a diamond is partially dissolved during transport?
• Which term describes the bending of light as it travels from one material to another?
• Which property is described as an efficient visual test for diamond identification?
• Which technique is best for determining whether a diamond is Type IIa or Type IIb?
• What is true about the use of masterstones in grading?
• Lamproite pipes form at which part of cratons?
• Which processes are critical to unveil a diamond's beauty and add value?
• True or False, Diamonds in jewelry are protected from damage.
• Which term describes the energy difference between the valence band and the conduction band?
• What factor increases the strain in a crystal?
• Which type of diamond contains boron in the lattice with negligible nitrogen?
• What often causes fluctuations in the diamond market?
• Which term denotes the characteristic crystal shape or form of a mineral?
• Most natural diamonds are classified as which type?
• What does spectroscopy study?
• Which set of components is required for CVD diamond growth?
• Where are secondary deposits located relative to their primary source?
• Lab-grown diamonds price is described as what relative to natural diamonds?
• Why is it difficult to develop a precise description of any clarity grade except Flawless diamonds?
• Which term describes the plane or surface in which a dislocation travels through the crystal to cause an offset?
• Which term describes the pattern of wavelengths absorbed by a material?
• Photoluminescence spectroscopy in diamond analysis primarily involves which observation?
• Table Gauge is a transparent measuring device divided into millimeters and tenths of a millimeter, used to measure which feature?
• Do all diamonds fluoresce under ultraviolet light?
• Why are diamonds without color centers colorless?
• Which term refers to placing and finishing facets on a rough diamond?
• What is the single most important value factor for a cuttable rough diamond?
• Which statement accurately describes the relationship between the emotional appeal and the practicality of fancy cuts?
• Which statement about diamond's thermal conductivity is correct?
• What color do you get when you irradiate and anneal a type Ib diamond?
• What is the basis for comparing a diamond's other proportions?
• Growth Sector is defined as which option?
• Which term is the regular, repeating arrangement of atoms in a mineral?
• Why do fancy cuts have different weight correction factors? What do they take in account?
• When submitting a cutting request, should jewelers provide angles or percentages?
• The GR1 defect can create blue color in diamonds when nitrogen concentrations are low.
• Which term corresponds to a grooved tray used for matching stones?
• In diamond, a group of five carbon atoms with one at the center is called what?
• As of now, which two groups supply more than half of the world's rough diamonds by value?
• Which analogy is used to illustrate color saturation in colored diamonds?
• What does natural diamond formation require?
• Note also that which items are not typically plotted on a GIA grade report?
• Compared with blade sawing, what is a true characteristic of laser sawing?
• Which term refers to minerals that form at great depths alongside diamonds and are brought to the surface by the same geological conduit?
• Which term refers to testing the size, shape, clarity, and color of diamonds in a deposit based on 500 tons of rock?
• Total Depth Percentage is calculated as which measurement?
• Recutting is defined as what?
• What largely governs the style of a diamond when it is recut?
• Which statement best describes the variability of fancy cuts?
• Which term denotes a vintage cushion-shaped brilliant cut characterized by a high crown, deep pavilion, 58 facets, and a large culet?
• What can affect a diamond's apparent appearance when viewing?
• Traceability in the diamond industry refers to the ability to track what from the mine to the end consumer?
• Which term is defined as the smallest group of atoms that defines the basic crystal structure and composition of a mineral?
• Which statement best captures the role of social media advertising for jewelers in the modern era?
• Non-round diamonds such as fancy cuts will what on grading reports?
• What should you know before recutting a diamond for sale?
• Isolated nitrogen is extremely difficult to remove from HPHT lab-grown diamonds because of what reason?
• Which statement about dispersion is true?
• Which statement best describes Type IIa diamonds?
• Crossed polarizers are best described as what?
• Which term is the exactness of a finished gem's shape and facet placement?
• What is eruption in geological terms?
• Which statement defines the band gap?
• Why is quality control essential for modern diamond cutting businesses?
• What is the term for the concentration of diamonds in a deposit, measured by the amount of diamonds in 100 tons of earth removed?
• What does FTIR spectroscopy measure in diamonds?
• Belly is defined as which of the following?
• Which simulant has slightly lower SG than diamond?
• What approach might some treaters take to achieve a specific body color?
• Which of the following is a listed environmental challenge in diamond mining?
• Laboratory-grown diamonds are defined as what?
• In diamond recovery, which term describes the final step after sizing and concentrating?
• True or False: With advanced instrumentation, the information gathered can conclusively identify a diamond.
• What does a Spectrometer do?
• What term describes the origin and history of ownership of a gemstone or piece of jewelry?
• Colored lamellae in gemstones are best described as?
• What is the critical angle of diamond?
• Why should girdles not be too thin?
• Which term is defined as the light returned when it hits a surface or a boundary between two different materials?
• According to the major concept for fancy-cut diamonds, which attribute is often the major selling point?
• Which term refers to the process of shaping a rough diamond into its basic face-up outline to prepare it for faceting?
• Which process recovers diamonds by separating them from lighter materials?
• What are Masterstones?
• A recovery process that separates diamonds from lighter materials using a dense medium is called what?
• Which term describes a crystal consisting of two or more parts formed in a symmetrical manner with shared crystal planes?
• Laser drilling targets what feature within a diamond?
• What does traceability mean in the diamond supply chain?
• Which materials commonly exhibit a vitreous luster?
• In reflection, what is the relationship between the angle of incidence and the angle of reflection?
• What is the main reason for the appearance of many colorless and colored CVD lab-grown diamonds?
• Which girdle characteristic can contribute to poor value by affecting face-up size?
• Which term is an environmental challenge associated with diamond mining?
• What can graders use to see inclusions hidden by prongs?
• Which country is home to the Surat diamond cutting center?
• Secondary diamond deposits typically require a bulk sampling parcel of approximately how many carats?
• Which decade marks the first time lab-grown diamonds were grown in a lab?
• Foilback refers to:
• Which description best matches carbonado?
• What is the angle at which light reflects off a surface called?
• How does repolishing compare to recutting in terms of weight loss?
• What does Major refer to in diamond industry terms?
• Metastable describes which concept?
• Which term describes the earth's surface and outermost layer?
• Which is rarer: diamond-bearing lamproite or kimberlite?
• If a color is described as having low saturation but the hue is strong, what is likely observed?
• Aside from color centers and defects, which factors can influence a diamond's color appearance?
• Hue is defined as?
• Which type of deposit has a higher percentage of gem-quality diamonds?
• Which term describes the process of forming the pavilion angle by gradually polishing off the extra material at different angles?
• Carbonado is the toughest form of diamond.
• Which layer contains the crust and the uppermost part of the mantle?
• X-Ray Separation uses X-rays to detect diamonds and which mechanism to remove them from the ore?
• How can laser drilling affect marketability?
• Which term refers to a lattice imperfection created when an atom is missing from its lattice position?
• Which term is defined as the price of a gem divided by its carat weight?
• What is the imaginary line perpendicular to a boundary surface called?
• What two inventions made mass production of faceted diamonds possible?
• Geologists look for secondary diamond deposits in which environments?
• In accurate clarity grading, what is considered regarding the size and shape of the diamond?
• What does Characteristic Color refer to in diamond grading?
• Why should you relate wholesale price estimates to your local market?
• Severe symmetry variations can be obvious to a viewer under what conditions?
• How do blemishes affect diamond grading, if any at all?
• Which term describes a crystal shape with eight equal triangular faces?
• Which statement best characterizes secondary deposits compared with primary deposits?
• What is a Single Cut in diamond cutting?
• Which statement best describes the factors that affect how clarity characteristics influence the clarity grade?
• Which cut was the basis for the full-cut modern brilliant?
• When using masterstones, how should they be applied and what condition must be met?
• Significant painting or digging out can give a diamond what effect?
• What should today's diamond retailers consider when planning strategy?
• Crown Height Percentage is defined as the distance from the girdle plane to the table, expressed as a percentage of which measurement?
• Which diamond plane is most efficient for sawing and dividing large, regularly shaped crystals?
• What do CVD diamond rough resemble?
• The diamond rush in South Africa began around which decade?
• Subadamantine describes:
• Girdle Thickness refers to which dimension of a diamond?
• Which statement best describes the origin of many colorless and colored CVD lab-grown diamonds according to the source?
• Rhinestone is a trade term used for diamond imitations made of glass or plastic, with or without foilback. Which option correctly pairs this term?
• What is the main color-causing mechanism in pink-to-red diamonds?
• Which term refers to the measure of how much light slows down and changes direction entering a material from air?
• Which term is a numerical expression of the relationship between length and width of a fancy cut, with width set to one?
• Which processes are typically included in the midstream phase?
• In business practice, what word describes the ability to continue an activity indefinitely?
• Photoluminescence Mapping is described as a PL mapping technique?
• On a standard diamond tester, which simulant can cause it to indicate diamond?
• Which description best defines a volume defect in a diamond?
• Which stones can have eye-visible inclusions?
• Do HPHT diamonds show a stronger fluorescence reaction to shortwave UV or longwave UV?
• What best describes a polarizer in gem testing?
• Why do major gem labs report features left by laser drilling as clarity characteristics?
• Interference colors are observed under cross-polarized light due to the interaction of two light rays. Which option best describes this?
• Which two factors of a bow-tie determine its effect on appearance?
• What is the theory of the formation, structure, and movement of the earth's landmasses?
• What unit are diamonds always measured in?
• Brilliant Cut is defined as?
• Open-pit mining is defined as what?
• Identify the term for a venue where companies market and sell goods and services to others.
• Saturation describes which aspect of color?
• What describes the Value-Adding Process?
• Which phrase is associated with the environmental impact categories for diamond mining?
• Which statement about girdle thickness is false?
• Inclusions can indicate where a diamond formed within the earth.
• Which proportions play the biggest role in determining a round brilliant diamond's brightness?
• Which term is defined as the angle of incidence at which the refracted ray is at 90 degrees?
• Which term is a notch scratched into rough diamond to prepare it for cleaving?
• Which of the following is NOT a standard category of defects in diamonds?
• X-Ray Separation is a recovery method that uses X-rays to detect diamonds and what to remove them from the ore?
• What do the interference colors reflect/represent?
• What type is the majority of CVD lab-grown diamonds?
• HPHT diamond crystal growth is predominantly which shape?
• Which term describes categories of crystals based on their symmetry and internal structure?
• Which Indian city is a prominent cutting center for diamonds?
• What colors can irradiation and annealing produce in a type Ia diamond?
• Are zircon and cubic zirconia considered the same simulant?
• Which property do standard diamond testers primarily measure?
• Sizing in the diamond recovery process is accomplished through a series of which actions?
• Typically the clarity factor that all clarity characteristics begin with is size. What other factors can affect the grade-setting characteristic?
• Which type of deposit has a higher concentration of diamonds?
• Which crystal planes are cleavage planes on a diamond?
• What is the main cause of black, gray, and white colors in diamonds?
• In photography, which statement defines exposure?
• If you are not certain of a stone's identity, what should you do?
• A cuboctahedron is defined as which type of crystal?
• If pavilion depth percentage is greater, the pavilion angle tends to be
• Which lighting condition should be avoided when trying to observe a diamond's fire?
• What does the term 'Visible Spectrum' refer to?
• Which lighting setup describes side lighting used to reveal clarity characteristics against a dark background?
• When saturation drops, how do cool and warm hues change?
• True or False, A mounting almost always limits your ability to assess a diamond.
• Which term denotes the price of a gem divided by its carat weight?
• Which term describes the disturbance of ecosystems and biodiversity caused by mining?
• Which statement about table size measurement is true?
• Most price lists quote prices on which basis?
• In diamond terminology, what is a blemish?
• What alternative sawing option is there for diamond rough with considerable strain?
• Which description best matches carbonate?
• Which term describes the reference system used to describe the symmetry and shape of crystals?
• Which statement best describes defense against simulant claims?
• Which phenomenon continues to emit light after the excitation stops?
• What best describes the Diamond Value Chain?
• Multi-Testers are:
• Total Depth Percentage is defined as which measurement?
• Heft describes:
• Cutting can alter a diamond's color appearance by changing what aspect of the light in the diamond?
• Which term refers to a flat, triangular twinned diamond crystal?
• Approximately how long did India serve as the world's only diamond source?
• Rhinestone describes:
• What was the Syndicate in the diamond industry?
• Which statement about carbon in diamond production is correct?
• Graphitization is defined as which description?
• What is Sorting Pad described as?
• Which term describes a solid matter with atoms arranged in a regular, repeating pattern?
• What is a crystal consisting of two or more parts formed in a symmetrical manner with shared crystal planes?
• Which statement best describes CVD diamond growth?
• Which best describes a Brilliant Cut?
• What makes it challenging to determine whether a diamond is natural or lab-grown?
• Diamond type is determined by what?
• The read-through test is reliable for which stones?
• What term describes the rate of temperature increase with depth in the earth?
• Which phenomenon explains the colored flashes seen in diamonds when light exits the stone?
• Which term defines a substance that increases the rate of a chemical reaction?
• What clarity characteristic can be a sign of efficient cutting?
• What percentage of natural diamonds are certified by the Kimberley Process?
• Which term refers to a holder that secures a diamond during processing?
• In fancy-cut diamonds, what is often the major selling point?
• How did Cecil Rhodes stabilize diamond prices?
• Which characteristics represent poor value because they appear smaller face-up?
• Which term describes a diamond that can be repolished to improve clarity to an Internally Flawless grade?
• In wave terminology, what is the wavelength?
• Which pair constitutes the two cut factors considered under the cut factor categories?
• Which statement about diamond and graphite is true?
• Culet size is defined as the size of which part of the diamond?
• Which technique is vital for colored diamond identification?
• Paste refers to:
• Which term describes the handling of mining waste and recycling processes?
• What are the three main steps of diamond recovery?
• Which term describes a diamond cut with a flat bottom and triangular facets that come to a point at the top?
• Which term is defined as a model in which the final sale price is based on the cost to produce the product plus a small markup?
• What primarily causes color in a diamond?
• What is a Scoop used for?
• Which two cut factors are considered under design?
• Which survey measures density variations to detect kimberlite or lamproite?
• Which statement best describes the HPHT color treatment in relation to HPHT diamond growth?
• Why is repolishing often performed after HPHT treatment?
• Which term describes a set of policies and processes that enable an organization to reduce environmental impacts and increase operating efficiency?
• Why is recognizing the demands of new consumer generations important for jewelers?
• Trade terms can refer to color or geographic origin in a non-objective way. Which statement is accurate?
• What are some major challenges diamond retailers face?
• The bruting machine is associated with which advancement?
• What made fancy brilliants easier to make and more affordable?
• How is a Secondary Deposit defined?
• Plot on a GIA grade report refers to what?
• When pricing a parcel of stones, which factor should you consider?
• Which term is the distance from the girdle plane to the table expressed as a percentage of average girdle diameter?
• What type of lighting is ideal for evaluating a diamond's brightness and scintillation (pattern)?
• Which term is listed as an environmental challenge in diamond mining?
• Which cut is widely considered the direct predecessor to the modern brilliant cut?
• Which statement describes factors other than the 4Cs affecting the retail price of a polished diamond or diamond jewelry?
• Which aspect is considered one of the most important in the GIA Diamond Grading System?
• Which term refers to the arrangement of atoms that creates symmetry and internal organization in a mineral?
• Selective absorption describes which process?
• What lighting condition is most widely accepted for color grading?
• Which statement best describes the scope of traceability in diamonds?
• Which term describes the force required to produce distortion in the crystal lattice?
• A trigon's presence on a diamond most directly indicates the presence of which crystal plane?
• Which statement best describes the primary difference between HPHT color treatment and HPHT diamond growth?
• Materials with higher refractive indices have smaller critical angles than materials with lower refractive indices.
• Which term defines complete reflection of a light ray within a material?
• Which term refers to the layer between the upper and lower mantles?
• What does girdle thickness guideline indicate about proper girdle thickness?
• Which term describes the relative size, arrangement, and contrast of bright and dark areas when viewed face-up?
• On the D-Z color scale, what do the letters denote, and what does each masterstone indicate regarding color?
• The majority of mined diamonds are formed in which formation types?
• Which system is the universal standard in the jewelry industry for color?
• The layer that contains the crust and the uppermost mantle is the:
• Who later expanded the idea of price stability by selling through a single channel and limiting the number of diamonds on the market according to demand?
• Which term describes the seed used to initiate HPHT growth?
• How many cut factor categories exist, and which two are among them?
• Which clarity factor usually has the greatest influence on the clarity grade?
• What describes relief in diamonds?
• What should be the ultimate reconsideration when recutting a diamond?
• Which statement best describes the influence of the host's habit on a negative crystal's crystallographic shape?
• How does fracture filling reduce visibility of fractures and cleavages?
• Which secondary diamond deposit is created by rivers or streams carrying diamonds to the shoreline or ocean floor?
• Black color in a diamond is most commonly caused by what?
• Which statement best describes a volume defect in a diamond?
• What term refers to a large downward-protruding portion of the lithosphere under a craton?
• To what extent should the color grading environment influence the grading outcome?
• What does a UV-Vis-NIR spectrometer do, and what is it vital for?
• What happens when an irradiated diamond is annealed?
• Approximately how many segments define the diamond value chain?
• How do you identify assembled simulants?
• Which statement accurately describes the Master-Eye Effect?
• One of the earliest methods used to modify diamond color was?
• Which term describes the horizontal tunnel through a diamond-bearing pipe?
• Vitreous describes the appearance of which surface?
• What does Stone Paper refer to in diamond handling?
• Which action is recommended when you are not certain of a gem's identity?
• During HPHT treatment, which phenomenon can occur that affects the diamond's structure and color?
• Which term describes a person who studies the diamond rough, develops cutting plans, and marks the plans on the rough?
• Which two igneous rocks transport diamonds to the surface?
• Depth of Color is defined as the combination of which two color properties?
• Which factor represents the category of environmental impact including energy use and emissions in diamond mining?
• When does GIA recommend repolishing diamonds?
• Which statement about laboratory-grown diamonds is accurate?
• Which term best defines a group of people united for a similar purpose in business?
• Which statement about the popularity of CZ as a simulant is accurate?
• Which instrument is commonly used to determine color origin in diamonds?
• Beyond size, which factors can affect the grade-setting characteristic in clarity evaluation?
• Which colors indicate radiation damage in natural diamonds?
• What is the force required to produce distortion in the crystal lattice?
• Which crystal planes are cleavage planes on a diamond?
• Which statement about inclusions is true?
• Networking can provide opportunities to succeed within your industry by doing what?
• Which statement best describes a growth sector in crystallography?
• True or False: Simulants can be natural or human-made.
• Which country was the only dominant diamond source until the early 18th century?
• What is a useful guide to a particular fancy cut's identifying characteristics?
• Color-causing defects create absorption by forming energy steps within the band gap. Which statement describes this process?
• Which term is defined as a crystal shape with eight equal triangular faces?
• Blue HPHT diamonds often phosphoresce what color?
• Which of the following is not explicitly listed as a necessary component for HPHT diamond growth?
• Digging Out is the cutting technique that thins the area of the girdle where the upper half facet junctions meet the lower half facet junctions? Which term describes this technique?
• What is a Sight in rough diamond trading?
• Most diamonds have symmetry variations, but the variations rarely affect appearance. True or False?
• Who assumed the De Beers chairmanship and formed the CSO after the Great Depression?
• Historically, diamonds were first discovered in India, then Brazil in 1729. Which country was associated with discoveries in 1869?
• Craftsmanship is defined as what?
• Which statement about the term 'feather' is accurate?
• What is key to developing accurate weight estimation?
• Which segment has the most risk and unpredictability in the diamond value chain?
• Which term refers to a long-term agreement in which a dealer or manufacturer loans goods to a retailer?
• What does the GIA Diamond Grading System provide?
• Most round brilliants have table percentages range from which of the following?
• Which diamond grading system is the most adopted today?
• What 16th-century developments shifted diamond cutting to genuine faceting?
• Which feature is a triangular depression or protrusion on a diamond's octahedral faces?
• What is the best way to see a diamond's fire?
• When evaluating a potential diamond deal, with what should you become familiar?
• Which statement about fluorescence under longwave UV is true for CVD lab-grown diamonds?
• What is the term for the most common twinned diamond crystal form?
• What is the Sieve Set?
• What platform for trading polished diamonds has emerged as a result of the Internet?
• What is a Sightholder?
• What instrument helps gemologists observe a diamond's absorption spectrum?
• Which cutting style is described by long, narrow, four-sided facets in rows parallel to the girdle on both crown and pavilion?
• How are color grades assigned to fancy cuts?
• What is the foundation of the diamond type classification system?
• The GIA Cut Grading System applies to which diamonds?
• Irradiation is defined as which description?
• Diamonds form mainly in two types of rocks. One is peridotite. What is the other?
• What element are diamonds and graphite composed of?
• Star Length Percentage measures the length of the star facets expressed as a percentage of which distance?
• Which description matches a horizontal tunnel drilled through a diamond pipe?
• A deep vertical formation at the earth's surface that results from a kimberlite or lamproite eruption is called a:
• Which statement about electronic scales is correct in gemstone practice?
• What caused a shift in emphasis from secondary to primary diamond mining?
• Internal Laser Drilling is a clarity treatment that uses a laser to enlarge existing cleavages or create new ones, providing a path for a bleaching solution to dissolve the inclusion.
• Crustal diamond forms where?
• The name De Beers is derived from what?
• Which statement best describes production and cost of diamond simulants compared to diamonds?
• After advanced testing, what is typically required to reach a final identification?
• Describe how CVD diamonds grow and what their layers are composed of.
• Which mining technique describes an underground method where orebody is drilled beneath the surface, loosened, and collected as it falls?
• When light travels from a more refractive material to a less refractive material, how does the refracted ray bend?
• A planar surface along which a mineral tends to break due to atomic weakness:
• In addition to symbols, how are clarity characteristics denoted on a grade report?
• Which country is a top diamond producer in terms of both value and volume?
• What is a Matching Tray used for?
• Which element is identified as important for successful buying and selling in the market?
• What kind of diamond forms can be caused by resorption?
• Which feature of a diamond reveals nearly all of the cutter's fashioning choices?
• Which term describes the process of dividing rough diamond along its cleavage planes?
• A primary deposit is defined as which of the following?
• Severe painting and digging out result in which outcome?
• Annealing is defined as which of the following?
• Which faceting style replaces the large bezel facets at the points of marquises, pears, and hearts with star and upper half facets?
• Which instrument measures both thermal and electrical conductivity to differentiate diamonds and simulants?
• Primary diamond deposits typically require a bulk sampling parcel of approximately how many carats?
• What is laser drilling?
• Which statement correctly describes the refractive index (RI) of air and gem materials?
• Crown Angle is the angle formed by which features?
• Which term is used for screening the presence of tiny diamonds in a sample?
• Which phenomenon causes white light to separate into spectral colors?
• As of now, which two markets are the top jewelry-consuming markets in the world?
• Recutting can be used to refashion a diamond after it's been damaged, though you can greatly lose carat weight when doing so.
• Which term refers to atoms in a gem that aren't part of its essential chemical composition?
• What happened to Argyle Diamond Mine in November 2020?
• How do color defects work in relation to a diamond's band gap?
• How did De Beers solidify its single-channel marketing strategy?
• Type IIb diamonds are characterized by...
• Which term denotes the geometric shape of a well-formed crystal?
• Mantle keels are commonly associated with diamond formation because they provide what kind of conditions?
• A Parcel is defined as which of the following?
• How do you determine a round brilliant diamond's table size?
• In grading, what is the role of environmental control?
• What term describes an imperfection or deviation from the ideal arrangement of atoms along a line in the crystal lattice?
• What does the Sieve Set describe?
• In comparison to recutting, repolishing takes a lot less weight.
• Which layer lies between the earth's crust and its core?
• Which term describes the process by which light that is not absorbed by a material returns to the observer?
• The GIA Cut Grading System is based on what?
• In luminescence after stimulation, the emitted energy is what relative to the exciting radiation energy?
• Which statement about pipe deposits is true?
• Sustainability in the gem and jewelry industry usually involves which considerations?
• Which term refers to screening for the presence of tiny diamonds in a sample?
• Are defects in diamond common, and are they always undesirable?
• Where is the majority of the world's diamond production cut and polished?
• What is brightfield illumination?
• Recognizing a market trend early can yield what kind of opportunity?
• Which minerals form along with diamonds at great depths and are brought to the surface by the same kimberlite or lamproite?
• The outward curve of the pavilion facets in a step-cut diamond is known as?
• Which term defines the ratio of the weight of a material to the weight of an equal volume of water?
• Irradiation of a type 1 diamond creates what bodycolors?
• Which era introduced continuous rotary motion and a cast-iron polishing wheel that shifted cutting toward faceting?
• A shallow crown can have which of the following effects?
• What is appraisal in the context of diamonds?
• Which term relates to water usage in mining operations?
• Which term describes a diamond that is a flat, triangular twinned crystal?
• With practice, table size estimation techniques can be described as?
• Which term describes a premium price paid for selecting stones from a parcel?
• What can affect a diamond's apparent appearance when viewing it?
• Between which adjacent grades is the biggest price difference observed when all other factors are equal?
• In which clarity category are inclusions typically visible to the unaided eye?
• Which term refers to the diamond's overall attractiveness relative to others of the same shape and cutting style?
• Which term describes a class of chemical compounds containing carbon and oxygen?
• What does Polish describe in a finished diamond?
• How does the energy of light relate to its wavelength?
• Which term refers to a long-term agreement in which a dealer or manufacturer loans goods to a retailer?
• Dealers usually offer better prices for immediate payment in full. Which option reflects this?
• Brazil's diamonds are mined predominantly from which deposits?
• In the law of reflection, which statement is true about the relationship between the angle of incidence and the angle of reflection?
• What is the smallest group of atoms with the characteristic chemical composition and the basic crystal structure of a mineral?
• What equipment can be used to see the characteristic terrace and riser growth sectors in CVD lab-grown diamonds?
• Which term refers to the conditions of a sale stating how and when an invoice is paid?
• Which term describes a model in which final sale price is based on the cost to produce the product plus a small markup?
• Which statement best defines an inclusion?
• What interaction is primarily responsible for most selective-absorption colors seen in gems?
• How does absorption affect color in colored diamonds?
• Which term describes the imaginary line perpendicular to a boundary, used as a reference in angle measurements?
• What are the only internal inclusions an HPHT lab-grown diamond may contain?
• Brazil's leading status as a diamond producer ended when diamonds were found in which country?
• Overburden refers to which of the following in diamond mining?
• Today the majority of diamonds are produced in four main regions. Which are they?
• Traceability in the diamond industry is defined as which of the following?
• Which term refers to the width of a fashioned gem's girdle?
• How would you describe the portion of the electromagnetic spectrum that is visible to the human eye?
• A smooth, flat break in a crystal parallel to a cleavage plane is called:
• Which country led diamond production from the early 1700s to the late 1800s?
• What is the effect of HPHT processing on a type Ia diamond?
• Describe the strain pattern of HPHT lab-grown diamonds, if any.
• How should your first impression of a diamond's face-up appearance influence its clarity grade?
• Which of the following is NOT a sign of fracture filling?
• Which term refers to the overall condition of the facet surfaces of a finished diamond?
• How common are diamondiferous kimberlites or lamproites?
• What diamond cuts followed the shape of the octahedral diamond rough?
• What is the most common color cause of green color in diamonds?
• Who established De Beers Consolidated Mines Ltd. in the late 1800s?
• Bulk Sampling is defined as large-scale character sampling of how many tons of rock?
• What is the upper wavelength bound commonly associated with the visible spectrum?
• What is a natural, inorganic substance with characteristic chemical composition and usually structure?
• Which statement about bow-ties is true regarding brightness impact?
• What does staying up to date with the diamond industry involve?
• Which term refers to a holder that secures a diamond during processing?
• Which term describes the length of the star facets expressed as a percentage of the distance from the girdle to the edge of the table facet?
• What is DiamondView primarily used for?
• Diamond synthesis research began before which year, and lab-grown diamonds were first grown in a lab in which decade?
• Under what conditions do CVD diamonds grow? How are they grown? What is required in the CVD process?
• What is the most popular diamond simulant on the market?
• How are simulants' girdles sometimes textured to mimic bruted diamonds?
• What optical phenomenon describes white light separating into spectral colors?
• Which term defines a substance that increases the rate of a chemical reaction?
• Which statement correctly defines CLIPPIR Diamonds?
• Which term describes a defect that can influence absorption of visible light to produce color?
• Which practice helps professionals navigate simulants?
• Which cut is the dominant diamond cut in today's market?
• What is the primary sales channel for rough diamonds?
• Recutting a round brilliant S-Z diamond into a fancy yellow radiant cut affects color because...
• What does the crust refer to?
• How do you identify color coating on simulants?
• What best defines a Primary Deposit in diamond geology?
• Which term most specifically denotes emission of light immediately during exposure to radiation?
• For buyers seeking something unique, would they prefer a round brilliant cut diamond or a fancy cut diamond?
• The Star of South Africa was discovered at Zandfontein on the banks of which river?
• If a publication focuses on news and trends in a specific industry, what term describes it?
• Which campaign helped establish the global tradition of the diamond engagement ring, including the slogan 'A diamond is forever'?
• What distinguishes Type I diamonds?
• True or False: Today, there's equal interest in maintaining or creating old-style cuts and in recutting them as modern brilliants.
• How can HPHT treatment of type II diamonds affect color?
• Phosphorescence is the continued emission of light after exposure to UV or X-ray stimulation stops. Which option best expresses this?
• Interference colors are observed under cross-polarized light as which description?
• Laser bruting is especially helpful for what kind of diamond manufacturing?
• What are the three cut factor categories and how many cut factors are there?
• What is a Tang?
• Which cut provided an efficient way to use flattened or cleaved rough?
• Which part makes a significant contribution to a diamond's brightness and fire?
• Which term describes the combination of tone and saturation?
• Which crystal growth shape is most commonly associated with HPHT diamonds?
• Which term best describes a solid mass of individual randomly oriented crystals held together by a natural binding agent?
• Why do cutters apply the brilliant cut to fancy shapes?
• How do diamond cut trends change?
• Superdeep Diamonds are defined as diamonds that formed at what depth beneath the earth's surface?
• What does the term 'feather' refer to in diamond terminology?
• Where were Indian diamonds historically mined?
• Which term describes possessing different physical or optical properties in different crystal directions?
• What is one stated economic benefit of diamond mining in remote areas?
• Blue and colorless HPHT lab-grown diamonds often phosphoresce color?
• Which term means possessing the same physical or optical properties in all crystal directions?
• Which term is a magazine, newspaper, journal, or website sharing industry news and trends?
• Which term describes a point defect created when an atom is missing from its original position in the crystal lattice?
• In gemology, which term refers to a defect that can influence absorption of visible light?
• Thermal Tester is a device that:
• Accurate clarity grading is usually determined by what?
• Many colors that are called grays are actually what in relation to various hues?
• Which of the following would be considered a sign of fracture filling?
• Which term is defined as the act of shaping the rough into its basic outline before faceting?
• What combination of things does modern planning technology benefit from?
• Which term describes an early cushion-shaped brilliant cut with a high crown, deep pavilion, 58 facets, and a large culet?
• Which optical property primarily causes a diamond's fire?
• What kind of advances impact the entire diamond supply chain?
• The Macle is the most common twinned diamond crystal form.
• Which country was identified as the third-largest diamond producer in terms of both value and volume?
• Which term refers to an analysis that determines the chemical composition of a sample?
• What can affect the color resulting from irradiation?
• Which set of elements are used to describe color in GIA grading?
• What characterizes the downstream phase of the diamond value chain?
• Which combination of factors can influence color appearance aside from color centers and defects?
• What is a Doublet in gemology?
• Masterstones define color grades in which range?
• Which statement about relief is supported by the relationships described for relief characteristics?
• Traceability in the diamond industry is primarily about which of the following?
• Which term refers to imperfections that extend along a line in the crystal lattice?
• Which description best defines fluorescence in gemstones?
• Which term best describes the surface's appearance under reflected light?
• What is the purpose of a culet on a diamond?
• Eye-Visible is defined as what in diamond grading terms?
• What is the Secondary Market?
• What is the most common habit (crystal form) of a gem diamond?
• Price lists estimate wholesale diamond prices in a specific market, so what should buyers understand about these estimates?
• Which two components does modern planning technology combine to optimize planning?
• How many directions should you check for doubling?
• Which term describes visible shadow-like lines in a diamond caused by glide planes?
• What is Sorting Pad used for?
• Belly is defined as?
• In terms of processing advantages, laser sawing over traditional blade sawing is most accurately described as which?
• What limited the use of lab-grown diamonds in jewelry from the 1990s to the early 2000s?
• Most CVD lab-grown diamonds cannot be identified using standard gem-testing equipment and must be submitted to a laboratory for identification. What must be done to verify their identity?
• A chemical bond formed by two atoms sharing electrons is:
• Which of the following describes fracture filling?
• The main color cause in pink-to-red diamonds is deformation-caused selective absorption.
• What is the toughest form of diamond?
• Why do moissanite testers use a different method from standard diamond testers?
• Which of the following is not listed among the four main diamond-producing regions today?
• Which statement best describes how light speed changes with refractive index?
• What term is defined as the arrangement of a gem's facets?
• Naturally irradiated diamonds usually contain areas of green or brown radiation damage on their surfaces or penetrating into the stones.
• Laser bruting is especially helpful for which category of diamond manufacturing?
• Which property do moissanite testers test to distinguish from diamonds?
• What limits the number of players in the upstream segments of the diamond value chain?
• Before the invention of mechanized bruting, which diamond shape was easier to cut?
• What best describes trade terms in the diamond industry?
• Which term refers to a well-shaped, transparent octahedral diamond crystal with sharp, square edges?
• What is the meaning of Beneficiation in the context of mineral resources?
• Colorless HPHT lab-grown diamonds are typically which type?
• In diamond processing, Recovery is best described as which of the following?
• Before the 15th century, what was diamond cutting limited to?
• What were popular diamond simulants in the 1990s?
• Which statement best captures why the appeal of a fancy cut can be valued?
• Which term groups crystals by symmetry and internal structure?
• Most Type I diamonds are a mix of more than one diamond type.
• Is an estimate of a diamond's pavilion depth percentage usually accurate enough for grading and appraising?
• Which rock type is formed from a molten state?
• Which factors must lab-grown diamond producers consider?
• Which statement best describes modern silica coatings on diamonds?
• What does Upstream refer to in the diamond value chain?
• What is the term for any molten rock within the earth?
• Bearding is defined as...
• Which mechanism uses diamond's affinity for grease to separate diamonds from other minerals?
• Which term describes the chemical alteration of rocks due to introduction of external materials such as fluids or melts?
• Which term identifies the boundary condition at which total internal reflection begins?
• When light passes from a less refractive material to a more refractive material, how does the refracted ray bend relative to the normal?
• Photoluminescence spectroscopy is noted for detecting what with extremely high precision?
• What is the most common method of underground diamond mining?
• Which term describes a diamond with a flat, triangular shape resulting from twinning?
• What is a simulant in diamond terminology?
• A negative crystal's crystallographic shape always mimics the habit of the host. Which of the following best describes this relationship?
• Which term denotes an imperfection or deviation from the ideal crystal lattice?
• What does repolishing a polished diamond refer to?
• Average Girth Diameter is defined as the mean of the smallest and largest diameter measurements of a round brilliant.
• Rough diamond auctions (tenders) provide an opportunity for which group to source directly from producers?
• What is the primary goal of colored diamond color grading?
• Most diamonds mined today originate from which type of deposit?
• What is an event where businesses promote and sell their products and services?
• What is a key economic implication of diamond mining in remote areas?
• Which statement best describes an absorption spectrum in gems?
• Before 2010, lab-grown jewelry diamonds were characterized by which combination of traits?
• What does exposure refer to in photography?
• What does the term Electromagnetic Spectrum refer to?
• Which term is a notch scratched into rough to prepare it for cleaving?
• Which of the following lists the seven cut factors?
• Table Percentage expresses what aspect of a diamond?
• Which term denotes the concept of exchanging information and developing contacts among people with a common professional or special interest?
• Most Brazilian diamonds come from which type of sources?
• Which term is an imperfection or deviation from the ideal arrangement of atoms in relation to a single atom or point in the crystal lattice?
• Improvable means what regarding a diamond's ability to improve clarity?
• Which of the following describes the Transition Zone?
• Before 2010, lab-grown diamonds used in jewelry were primarily characterized by which of the following?
• Painting is a cutting technique that thins which area?
• What is the Earth's core?
• The perfectly shaped octahedral rough is described as what?
• What are the two major commercial technologies for synthesizing lab-grown diamonds?
• What kind of loupe is important for diamond grading and what does it correct?
• What is the most common cause of yellow color in diamonds?
• Alluvial deposits concentrate gems in which environment?
• White light consists of what?
• How do HPHT color treatment and HPHT growth compare in processing time?
• Finish refers to which aspect of a diamond?
• Which cut factor is most likely to cause a dull, hazy appearance if poor?
• What does the secondary market indicate about a diamond's value?
• Which of the following is an example of high relief clarity characteristics?
• Where are the highest profits realized on the diamond value chain?
• Grade-Setting Characteristics are best described as what?
• What term refers to colorless lines or grooves on a diamond crystal's surface?
• Which area has the most diverse diamond sources?
• Which term means exchanging information and developing contacts among people with a common professional or special interest?
• In CVD diamond growth, what is the substrate?
• True/False: Diamond simulants have improved over time, but older simulants may still be seen.
• What is a core purpose of the color grading system for professionals?
• Which factor is not listed as a factor affecting how clarity characteristics influence the clarity grade?
• For fancy colored diamonds, what orientation is used when grading color because cut can influence color?
• Alluvial Deposit is defined as a deposit where gems are eroded from their source rock and transported away from the source and further concentrated in rivers and streams.
• What is depth of field in gemology?
• Which phase of the diamond value chain includes mining and sorting rough diamonds?
• Which statement correctly identifies the strongest type of atomic bond and a related characteristic of diamond?
• Which term describes the smallest group of atoms that defines the basic crystal structure and composition?
• What is sawing in diamond processing?
• Under what condition can irradiation color change occur unintentionally?
• Which country is known for having the largest marine diamond deposit in the world?
• Which girdle thickness percentage is outside the range for an excellent cut grade?
• Foilback is described as:
• Which direction is easier to polish?
• Brillianteering describes...
• What is the primary purpose of post-growth treatment in CVD lab-grown diamonds as described?
• Which term refers to the highest degree of luster in a transparent material?
• Which statement describes the effect of 16th-century developments on diamond cutting?
• What do many trade shows offer to help attendees stay current with industry knowledge?
• Which term describes repairing damage or refashioning a polished diamond to improve its clarity, proportions, or color, or to modernize an old-style cut?
• Most diamond screening devices are based on the fact that the majority of natural diamonds are which type?
• Which of the following do many trade shows offer to help attendees stay up to date with the industry?
• Which term best describes a rock formed from molten material that has cooled and solidified beneath the surface or after eruption?
• Which statement about plotting is accurate with respect to GIA grade reports?
• Which statement best describes the role of the internet and social media in jewelry retail today?
• What luster is typical of non-diamond simulants and among the best?
• What does fracture filling involve?
• What color is commonly produced by irradiation and annealing of a type Ia diamond?
• Which statement best describes repolishing in relation to recutting?
• What term do diamond professionals use to describe a diamond's display of dispersion?
• What could affect the accuracy of estimated carat weight in a diamond?
• Paste describes:
• Which statement best reflects the visibility of symmetry variations?
• What are the three common categories of defects in diamonds?
• Traceability best describes its purpose as which of the following?
• Which description best defines subduction?
• What is the Master-Eye Effect?
• Sizing refers to which processing step?
• Which statement about Argyle mine is accurate?
• What term refers to visible features on the surface of a mineral crystal that reflect its internal growth and development?
• What are two major challenges facing diamond mining companies?
• DiamondView can be used to observe what in diamonds?
• Digging Out is a cutting technique that thins which area to retain weight or remove clarity characteristics?
• Which of the following is an example of low relief in clarity characteristics?
• Tone describes what aspect of color?
• What do market professionals typically use to estimate wholesale prices in a market?
• Which term describes the model in which manufacturers charge the highest initial price that customers will pay and lower it over time as new competitors enter the market?
• What is a common drawback of a thicker girdle?
• Which term is used to describe the geometric factor of a well-formed crystal’s external form?
• Which statement accurately describes Earth's basic structure and mantle division?
• Which statement best describes India's role in diamond cutting and polishing?
• Design is defined as what in diamond evaluation?
• Which term denotes a short-term agreement in which a dealer entrusts goods to a client without requiring immediate payment?
• Which term describes large, ancient, stable parts of the earth's landmasses?
• What statement correctly describes the relationship between diamond color and its crystal lattice?
• Coning is commonly done on round-shape diamonds. What is its main purpose?
• What does Path Length refer to in gemstone optics?
• Alluvial deposits are defined as deposits where gems are eroded from their source rock and then transported away from the source and further concentrated in rivers and streams.
• Which statement about the crystal planes present in diamonds is true?
• Which term defines the exactness of a finished gem's shape and facet placement?
• In accurate clarity grading, how is the size of the diamond considered?
• What contributed to the breakdown of De Beers' single-channel marketing system in the mid-1990s?
• Is disclosure of fracture filling an industry requirement?
• Which term describes distortion or deformation in a crystal lattice?
• A Shaft in mining is best described as which of the following?
• Which statement distinguishes a blemish from an inclusion?
• Which statement is true about zircon and cubic zirconia in the context of diamond simulants?
• Which term describes a material made of crystals or having crystallinity?
• Geologists focus the search for primary diamond deposits on which geological feature?
• What is the practical purpose of diamond rough mapping in modern planning?
• Which region hosts the world's most diverse diamond sources?
• What do trigons indicate on a diamond?
• In relation to most simulants, how does diamond's SG and heft compare?
• In photon energy terms, which statement is correct regarding wavelength?
• One of the three cut factor categories includes polish and symmetry. Which statement is correct?
• Which statement best describes the effect of Internet-enabled platforms on polished diamond trading?
• How are clarity characteristics used by gemologists and graders in relation to a stone?
• Which term means composed of crystals or related to crystals?
• The D-to-Z color range refers to which attribute?
• Which term describes a secondary diamond deposit formed by rivers or streams delivering diamonds to shorelines or the ocean floor?
• Which feature is typically mined for primary diamond deposits?
• Which term describes a diamond cut with a flat bottom and triangular facets that come to a point at the top?
• Which statement about the evolution of diamond simulants is correct?
• Each cut grade includes a range of what?
• Reflection best occurs on which type of surface?
• Which country is home to ALROSA, the major diamond producer that bypassed the CSO?
• Average Girth Diameter is defined as the result achieved by adding the smallest and largest diameter measurements of a round brilliant and dividing by two.
• In the grading process, what is the correct approach to masterstones relative to grading requirements?
• Slight color differences could have what impact on a diamond's value?
• What is the most reliable and precise determination of diamond type?
• Which statement about depth of field and magnification is true?
• What is the flash effect in fracture-filled diamonds?
• Which term describes the angle at which light hits a surface, measured with respect to the normal?
• Potential means what regarding a diamond's ability to improve clarity?
• Bowtie is defined as?
• What best defines a rock?
• Which statement about bruted girdles is true?
• Identify the cutting style with long, narrow, four-sided facets in rows parallel to the girdle on both the crown and pavilion.
• Does the heft test work for mounted stones?
• What conditions do HPHT diamonds replicate?
• Which term describes something currently in demand or popular among consumers?
• A cuboctahedron is defined as which of the following shapes?
• Kimberlite pipes tend to occur in which part of cratons?
• Market awareness helps you do what in business?
• Geologically, where are most diamond deposits found?
• Why does longer path length affect color saturation in a gemstone?
• Interstitial Positions are defined as what?
• Which country provides about one third of the world's rough diamond supply?
• Which statement best describes selective absorption in visible light?
• Which statement describes Photoluminescence Mapping?
• What is one primary benefit of the GIA color grading system for professionals?
• Which statement accurately describes how color origin is determined in gemological laboratories?
• Which process involves chemical changes in minerals and rocks resulting from introduction of external sources such as fluids or melts?
• Which statement about graphitization in diamonds is correct?
• Blocking refers to ...
• Which statement best defines a clarity characteristic?
• Which cutting style combines step-cut and brilliant-cut facets?
• Is it possible to estimate diamond color, and how accurate can the estimate be?
• In modern planning, how do rough mapping and computer-aided planning relate?
• In repolishing, what is the ultimate relationship to weight compared to recutting?
• What is the primary purpose of the Kimberley Process?
• What is Vertical Integration?
• Which statement best describes light in terms of energy and propagation?
• Which term refers to a diamond that forms in the continental crust near the earth's surface due to meteorite impact or tectonic plate collision?
• Which term defines any set of parallel and evenly spaced planes distributed along certain crystal directions in which atoms are more closely packed?
• What is more important: how a diamond actually looks or its numerical parameters?
• Luminescence is defined as which of the following?
• What is the correct characterization of the term 'simulant' in gemology?
• Which term best describes a shared, unalterable ledger used to record transactions and track assets through a supply chain or business network?
• Long-term contracts benefit both sellers and buyers due to which characteristic?
• Outward curve of the pavilion facets of a step-cut diamond is called what?
• True or False: No simulant mimics all of a diamond's features.
• HPHT lab-grown diamonds are produced by converting a solid carbon source to diamond with an HPHT press. Which set describes the required components for HPHT growth?
• The boron in natural blue diamonds originates from which source?
• A diamond's overall attractiveness in relation to others of the same shape and cutting style is called its what?
• What drives the movement of the Earth's plates, which is important to diamond formation?
• The face-up outline of a gem is known as its what?
• What is the lower wavelength bound commonly associated with the visible spectrum?
• Which description matches a Diamantaire?
• Which term describes the overall effect of light from a diamond's internal and external reflections?
• How do price levels in your market assist in evaluating a potential deal?
• What are cratons?
• Which of the following are examples of volume defects in diamonds?
• CVD growth occurs under which pressure conditions?
• In CVD diamond growth, what are the growth sectors called?
• What clarity characteristic must always be disclosed on a grade report and to a buyer when selling a diamond with this characteristic?
• Which term means the ability to continue a specific behavior indefinitely?
• Which diamond sparked the preliminary rush in 1866?
• Which term describes the ability of a medium to slow down light?
• Which term is defined as the ratio of the weight of a material to the weight of an equal volume of water?
• Which term denotes a discounted price for buying an entire parcel or a substantial part of it?
• In photography, which option correctly defines aperture?
• Which term refers to the set of planes that are parallel and evenly spaced along crystal directions?
• What term describes a rock that has been altered by heat and pressure?
• What negative effect does an excess pavilion bulge have on a step cut diamond?
• What is electrical conductivity?
• Which term is defined as a measure of the change in speed and direction as light travels from the air to a certain material?
• When saturation falls, what happens to cool hues?
• Which statement is accurate about pavilion depth percentage?
• The basic structural unit of all matter is which of the following?
• What does the HPHT treatment do to a diamond, and what post-treatment step is commonly required?
• What made rose cuts efficient for use?
• What describes a committee, club, society, or association united for a similar purpose?