Diamond & Diamond Grading Exam
1. Abrasion (Abr)ASW A series of minute nicks along the facet junctions of a fashioned diamond; gives the edges a white
or fuzzy appearance. (Assignment 10)
2. Adamantine lusterASW The highest degree of luster possible in a transparent mate- rial. (Assignment 8)
3. AggregateASW A solid mass of individual, randomly oriented crystals, intergrown or held together by a natural binding
agent. (Assignment 7)
4. Alluvial depositASW A deposit where gems are eroded from their source rock, then transported away from the source
and further concentrated. (Assignment 5)
5. Angle of incidenceASW The angle at which a ray of light strikes a surface, measured from the normal. (Assignment 8)
6. Angle of reflectionASW The angle between the normal and a reflected ray of light. (Assignment 8)
7. AnnealingASW Using heat to stabilize irradiated color in gemstones. (Assignment 12)
8. AppraisalASW An estimation of the value of an article, usually for insurance purposes. (Assignment 1)
9. Average girdle diameterASW The result achieved by adding the smallest and largest girdle measurements of a round
brilliant and dividing by two. (Assignment 14)
10. BastASW Frosted rough diamond. "Bark" in Dutch. (Assignment 9)
11. Bearded Girdle (BG)ASW Very small feathers that extend from the girdle surface into the stone; can result from
the cutting process. (Assignment 10)
12. BellyASW The slightly curving center of the long side of a pear, marquise, heart, or oval. (Assignment 16)
13. BeneficiationASW A commitment to reserve a portion of the resources derived from any country for the economic
development of that country. (Assignment 3)
14. Best Practices Principles (BPP)ASW De Beers' formalized commitment of itself and its sightholders to the highest
ethical standards. (Assignment 3)
15. BlemishASW Clarity characteristic that's confined to the surface of a polished gem- stone. (Assignment 10)
16. Block cavingASW Underground mining that involves building a concrete-lined tun- nel under an ore deposit, then
collecting the ore through openings in the liner. (Assignment 6)
17. BlockingASW Placing the first 17 or 18 facets on a diamond. (Assignment 9)
18. Bow-tieASW A dark area across the center of an elongated brilliant cut. (Assignment 16)
19. Brick-and-mortar retailerASW A traditional store consisting of walls and a fixed location. (Assignment 3)
20. BrightnessASW The effect of all the diamond's internal and external reflections of white light. (Assignment 8)
, Diamond & Diamond Grading Exam
21. Brilliant cutASW A cutting style in which triangular and kite-shaped facets radiate from a gem's center toward its
girdle. (Assignment 16)
22. BrillianteeringASW Placement and polishing of the star and upper and lower girdle facets. (Assignment 9)
23. Bruise (Br)ASW A tiny area of impact accompanied by very small, root-like feathers visible at 10X magnification;
typically occurs at a facet junction. (Assignment 10)
24. BrutingASW Forming the basic face-up outline of a diamond to prepare it for faceting. (Assignment 9)
25. Bulk samplingASW Large-scale character sampling. (Assignment 5)
26. Burn Marks (Brn)ASW Hazy surface areas that result from excessive heat or from uneven polishing caused by
structural irregularities; also called polish marks or burned facets. (Assignment 10)
27. Cavity (Cv)ASW An angular opening created when part of a feather breaks away. (Assignment 10)
28. Central Selling Organisation (CSO)ASW An agency designed to purchase, sort, evaluate, and sell rough diamonds.
(Assignment 2)
29. Character samplingASW Testing for the size, shape, clarity, and color of the dia- monds in a deposit. (Assignment
5)
30. Characteristic colorASW The basic color of a fancy-colored diamond. (Assignment 13)
31. Chemical vapor deposition (CVD)ASW An industrial process adapted to allow growth of synthetic diamond
from carbon-rich gas in thin layers onto a silicon or diamond surface. (Assignment 19)
32. Chip (Ch)ASW A shallow opening caused by damage to the stone's surface; typically occurs at a girdle edge, facet
junction, or culet. (Assignment 10)
33. Clarity characteristicASW Internal or external feature of a gemstone that helps determine its quality and
establish its identity. (Assignment 10)
34. Cleavage (Cl)ASW Large, severe, straight break along a plane of atomic weakness; considered an inclusion. (Assignment
10)
35. Cleavage planeASW Plane parallel to a possible crystal face, where a diamond can split cleanly when struck.
(Assignment 7)
36. CleaverASW A person who cleaves, or splits, a diamond along a cleavage plane. The cleaver might also be responsible
for planning the fashioning of a polished gem. (Assignment 9)
37. CleavingASW Dividing a diamond into two or more pieces along a cleavage plane. (Assignment 9)
38. Cloud (Cld)ASW Many tightly grouped pinpoints that might be too small to distin- guish individually at 10X but
together have a hazy appearance. (Assignment 10)
, Diamond & Diamond Grading Exam
39. Color centerASW Structural defect that influences an object's absorption of light and can cause its color. (Assignment
12)
40. Conflict diamondsASW Diamonds used to finance violence and terror. (Assignment 3)
41. ConsignmentASW A selection of goods loaned to a dealer by another wholesaler or manufacturer. (Assignment 20)
42. CoreASW Earth's innermost layer. (Assignment 4)
43. Covalent bondASW A chemical bond formed by two atoms sharing electrons. (As- signment 7)
44. CraftsmanshipASW The care that goes into the fashioning of a polished diamond, as confirmed by its finish.
(Assignment 15)
45. CratonsASW Ancient, large, and stable parts of the earth's continental crust. (As- signment 4)
46. Critical angleASW Angle between the normal and the maximum angle of refraction, which is the largest angle at which
rays inside the diamond can escape. (Assignment 8)
47. Cross workerASW A person who performs the cross-working operations during diamond polishing; sometimes
called a cross cutter. (Assignment 9)
48. Cross workingASW Placing the bezel and pavilion facets on round and fancy shapes. Sometimes combined with
blocking, especially on smaller stones. Also called cross cutting. (Assignment 9)
49. Crown angleASW The angle formed by the bezel facets and the girdle plane. (Assignment 14)
50. Crown height percentageASW The distance from the girdle plane to the table, expressed as a percentage of
average girdle diameter. (Assignment 14)
51. CrustASW The surface and outermost layer of the earth. (Assignment 4)
52. CrystalASW Solid matter with atoms arranged in a regular, repeating pattern. (As- signment 7)
53. Crystal (Xtl)ASW A mineral crystal contained in a diamond. (Assignment 10)
54. Crystal planesASW Internal directions parallel to a mineral's unit cell surfaces. (Assignment 7)
55. Crystal shape (form)ASW Geometric shape of a well-formed crystal. (Assignment 7)
56. Crystal structure (lattice)ASW Regular, repeating arrangement of atoms in a min- eral. (Assignment 7)
57. Crystal systemsASW Categories of crystals based on their symmetry and internal structure. (Assignment 7)
58. CrystallineASW Composed of crystals or related to crystals. (Assignment 7)
1. Abrasion (Abr)ASW A series of minute nicks along the facet junctions of a fashioned diamond; gives the edges a white
or fuzzy appearance. (Assignment 10)
2. Adamantine lusterASW The highest degree of luster possible in a transparent mate- rial. (Assignment 8)
3. AggregateASW A solid mass of individual, randomly oriented crystals, intergrown or held together by a natural binding
agent. (Assignment 7)
4. Alluvial depositASW A deposit where gems are eroded from their source rock, then transported away from the source
and further concentrated. (Assignment 5)
5. Angle of incidenceASW The angle at which a ray of light strikes a surface, measured from the normal. (Assignment 8)
6. Angle of reflectionASW The angle between the normal and a reflected ray of light. (Assignment 8)
7. AnnealingASW Using heat to stabilize irradiated color in gemstones. (Assignment 12)
8. AppraisalASW An estimation of the value of an article, usually for insurance purposes. (Assignment 1)
9. Average girdle diameterASW The result achieved by adding the smallest and largest girdle measurements of a round
brilliant and dividing by two. (Assignment 14)
10. BastASW Frosted rough diamond. "Bark" in Dutch. (Assignment 9)
11. Bearded Girdle (BG)ASW Very small feathers that extend from the girdle surface into the stone; can result from
the cutting process. (Assignment 10)
12. BellyASW The slightly curving center of the long side of a pear, marquise, heart, or oval. (Assignment 16)
13. BeneficiationASW A commitment to reserve a portion of the resources derived from any country for the economic
development of that country. (Assignment 3)
14. Best Practices Principles (BPP)ASW De Beers' formalized commitment of itself and its sightholders to the highest
ethical standards. (Assignment 3)
15. BlemishASW Clarity characteristic that's confined to the surface of a polished gem- stone. (Assignment 10)
16. Block cavingASW Underground mining that involves building a concrete-lined tun- nel under an ore deposit, then
collecting the ore through openings in the liner. (Assignment 6)
17. BlockingASW Placing the first 17 or 18 facets on a diamond. (Assignment 9)
18. Bow-tieASW A dark area across the center of an elongated brilliant cut. (Assignment 16)
19. Brick-and-mortar retailerASW A traditional store consisting of walls and a fixed location. (Assignment 3)
20. BrightnessASW The effect of all the diamond's internal and external reflections of white light. (Assignment 8)
, Diamond & Diamond Grading Exam
21. Brilliant cutASW A cutting style in which triangular and kite-shaped facets radiate from a gem's center toward its
girdle. (Assignment 16)
22. BrillianteeringASW Placement and polishing of the star and upper and lower girdle facets. (Assignment 9)
23. Bruise (Br)ASW A tiny area of impact accompanied by very small, root-like feathers visible at 10X magnification;
typically occurs at a facet junction. (Assignment 10)
24. BrutingASW Forming the basic face-up outline of a diamond to prepare it for faceting. (Assignment 9)
25. Bulk samplingASW Large-scale character sampling. (Assignment 5)
26. Burn Marks (Brn)ASW Hazy surface areas that result from excessive heat or from uneven polishing caused by
structural irregularities; also called polish marks or burned facets. (Assignment 10)
27. Cavity (Cv)ASW An angular opening created when part of a feather breaks away. (Assignment 10)
28. Central Selling Organisation (CSO)ASW An agency designed to purchase, sort, evaluate, and sell rough diamonds.
(Assignment 2)
29. Character samplingASW Testing for the size, shape, clarity, and color of the dia- monds in a deposit. (Assignment
5)
30. Characteristic colorASW The basic color of a fancy-colored diamond. (Assignment 13)
31. Chemical vapor deposition (CVD)ASW An industrial process adapted to allow growth of synthetic diamond
from carbon-rich gas in thin layers onto a silicon or diamond surface. (Assignment 19)
32. Chip (Ch)ASW A shallow opening caused by damage to the stone's surface; typically occurs at a girdle edge, facet
junction, or culet. (Assignment 10)
33. Clarity characteristicASW Internal or external feature of a gemstone that helps determine its quality and
establish its identity. (Assignment 10)
34. Cleavage (Cl)ASW Large, severe, straight break along a plane of atomic weakness; considered an inclusion. (Assignment
10)
35. Cleavage planeASW Plane parallel to a possible crystal face, where a diamond can split cleanly when struck.
(Assignment 7)
36. CleaverASW A person who cleaves, or splits, a diamond along a cleavage plane. The cleaver might also be responsible
for planning the fashioning of a polished gem. (Assignment 9)
37. CleavingASW Dividing a diamond into two or more pieces along a cleavage plane. (Assignment 9)
38. Cloud (Cld)ASW Many tightly grouped pinpoints that might be too small to distin- guish individually at 10X but
together have a hazy appearance. (Assignment 10)
, Diamond & Diamond Grading Exam
39. Color centerASW Structural defect that influences an object's absorption of light and can cause its color. (Assignment
12)
40. Conflict diamondsASW Diamonds used to finance violence and terror. (Assignment 3)
41. ConsignmentASW A selection of goods loaned to a dealer by another wholesaler or manufacturer. (Assignment 20)
42. CoreASW Earth's innermost layer. (Assignment 4)
43. Covalent bondASW A chemical bond formed by two atoms sharing electrons. (As- signment 7)
44. CraftsmanshipASW The care that goes into the fashioning of a polished diamond, as confirmed by its finish.
(Assignment 15)
45. CratonsASW Ancient, large, and stable parts of the earth's continental crust. (As- signment 4)
46. Critical angleASW Angle between the normal and the maximum angle of refraction, which is the largest angle at which
rays inside the diamond can escape. (Assignment 8)
47. Cross workerASW A person who performs the cross-working operations during diamond polishing; sometimes
called a cross cutter. (Assignment 9)
48. Cross workingASW Placing the bezel and pavilion facets on round and fancy shapes. Sometimes combined with
blocking, especially on smaller stones. Also called cross cutting. (Assignment 9)
49. Crown angleASW The angle formed by the bezel facets and the girdle plane. (Assignment 14)
50. Crown height percentageASW The distance from the girdle plane to the table, expressed as a percentage of
average girdle diameter. (Assignment 14)
51. CrustASW The surface and outermost layer of the earth. (Assignment 4)
52. CrystalASW Solid matter with atoms arranged in a regular, repeating pattern. (As- signment 7)
53. Crystal (Xtl)ASW A mineral crystal contained in a diamond. (Assignment 10)
54. Crystal planesASW Internal directions parallel to a mineral's unit cell surfaces. (Assignment 7)
55. Crystal shape (form)ASW Geometric shape of a well-formed crystal. (Assignment 7)
56. Crystal structure (lattice)ASW Regular, repeating arrangement of atoms in a min- eral. (Assignment 7)
57. Crystal systemsASW Categories of crystals based on their symmetry and internal structure. (Assignment 7)
58. CrystallineASW Composed of crystals or related to crystals. (Assignment 7)
