Answers
1. Abrasion (Abr) A series of minute nicks along the facet junctions of a fashione
diamond; gives the edges a white or fuzzy appearance.
(Assignment 10)
2. Adamantine luster The highest degree of luster possible in a transparent
material. (Assignment 8)
3. Aggregate A solid mass of individual, randomly oriented crystals,
intergrown or held together by a natural binding agent.
(Assignment 7)
4. Alluvial deposit A deposit where gems are eroded from their source rock, then
trans-
ported away from the source and further concentrated.
(Assignment 5)
5. Angle of incidence The angle at which a ray of light strikes a surface, measured
from the
normal. (Assignment 8)
6. Angle of reflection The angle between the normal and a reflected ray of light.
(Assign-
ment 8)
7. Annealing Using heat to stabilize irradiated color in gemstones.
(Assignment 12)
8. Appraisal An estimation of the value of an article, usually for insurance
purpos- es. (Assignment 1)
9. Average girdle diameter The result achieved by adding the smallest and largest
girdle mea-
surements of a round brilliant and dividing by two. (Assignment 14)
10. Bast Frosted rough diamond. "Bark" in Dutch. (Assignment 9)
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11. Bearded Girdle (BG) Very small feathers that extend from the girdle surface into the
stone;
can result from the cutting process. (Assignment 10)
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12. Belly The slightly curving center of the long side of a pear, marquise,
heart, or oval. (Assignment 16)
13. Beneficiation 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 De Beers' formalized commitment of itself and its sightholders
Principles (BPP) to the highest ethical standards. (Assignment 3)
15. Blemish Clarity characteristic that's confined to the surface of a
polished gemstone. (Assignment 10)
16. Block caving Underground mining that involves building a concrete-lined
tunnel
under an ore deposit, then collecting the ore through
openings in the liner. (Assignment 6)
17. Blocking Placing the first 17 or 18 facets on a diamond. (Assignment 9)
18. Bow-tie A dark area across the center of an elongated brilliant cut.
(Assign- ment 16)
19. Brick-and-mortar retailer A traditional store consisting of walls and a fixed location.
(Assign-
ment 3)
20. Brightness The ettect of all the diamond's internal and external
reflections of white light. (Assignment 8)
21. Brilliant cut A cutting style in which triangular and kite-shaped facets
radiate from a gem's center toward its girdle.
(Assignment 16)
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22. Brillianteering Placement and polishing of the star and upper and lower gird
facets. (Assignment 9)
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