GEM 230 QUIZ - Diamonds Flashcards
(301 cards)
1
Q
The large, stable parts of the earth’s continental crust are called A. plates. B. islands. C. shields. D. cratons.
A
cratons.
2
Q
A loupe used for clarity grading must be corrected for chromatic and A. size distortion. B. vertical distortion. C. spherical distortion. D. depth-of-field distortion.
A
spherical distortion.
3
Q
You should expect to pay more when you buy from a dealer A. on credit. B. in parcels. C. with cash. D. in large quantities.
A
on credit.
4
Q
On a well-made diamond, the girdle will
A. look like a knife edge.
B. have just enough thickness to prevent chipping.
C. show its reflection when viewed through the table.
D. increase the weight of the diamond without adding to its beauty.
A
have just enough thickness to prevent chipping.
5
Q
The three main components of the earth are the crust, mantle, and A. core. B. center. C. stratosphere. D. subduction zone.
A
core.
6
Q
All diamond simulants rank lower than diamond in A. hardness. B. dispersion. C. fluorescence. D. specific gravity.
A
hardness.
7
Q
Cecil Rhodes’ main competitor in his early attempts to control diamond production was A. Barney Barnato. B. Ernest Oppenheimer. C. the Diamond Trading Company. D. an independent diggers’ association.
A
Barney Barnato.
8
Q
When the rough has a frosty or non-transparent surface, the cutter can look for inclusions by
A. X-raying the stone.
B. laser sawing the stone.
C. sawing the stone on-center.
D. polishing a window to view the interior.
A
polishing a window to view the interior.
9
Q
Calculate the table percentage of a round brilliant with the following measurements:
Table measurements: 4.85 mm, 4.85 mm, 4.90 mm, 4.95 mm
Minimum and maximum girdle diameters: 7.95 mm, 8.07 mm
A. 59 percent
B. 60 percent
C. 61 percent
D. 63 percent
A
61 percent
10
Q
Which one of the following clarity characteristics might be found in a synthetic diamond? A. Xenocryst B. Metallic flux C. Garnet crystal D. Diopside crystal
A
Metallic flux
11
Q
Because the Australians believed the CSO’s marketing favored large stones over smaller ones, they
A. abandoned diamond mining.
B. discarded small, brown diamonds as mine waste.
C. turned to India for help in marketing their diamonds.
D. aggressively promoted jewelry set with their own tiny gems.
A
aggressively promoted jewelry set with their own tiny gems.
12
Q
Synthetic diamond is a
A. natural material that looks like diamond.
B. manmade material that looks like diamond.
C. manmade material with essentially the same physical, chemical, and optical properties as natural diamond.
D. manmade material made primarily of carbon forming in a different crystal system than natural diamond.
A
manmade material with essentially the same physical, chemical, and optical properties as natural diamond.
13
Q
Dealers who buy diamonds on memo
A. must belong to a dealers’ association.
B. can keep the stones until they are sold.
C. automatically get a 5 percent discount on the price.
D. have the opportunity to inspect stones before buying.
A
have the opportunity to inspect stones before buying.
14
Q
The most common impurity element found in diamond is A. iron. B. boron. C. carbon. D. nitrogen.
A
nitrogen.
15
Q
Oppenheimer’s answer to low diamond demand in the 1930s was to
A. advertise heavily.
B. reduce diamond prices.
C. shut down operations at De Beers mines.
D. stop buying diamonds from outside sources.
A
shut down operations at De Beers mines.
16
Q
The process of polishing the star and upper and lower half facets is called A. kerfing. B. lasering. C. blocking. D. brillianteering.
A
brillianteering.
17
Q
On emerald cuts, differences in the angles of the rows of pavilion facets cause A. wide corners. B. pavilion bulge. C. a bow-tie effect. D. a shortened culet.
A
pavilion bulge.
18
Q
In a stone with these clarity characteristics, which would probably be the grade-setting characteristic? A. Pit B. Feather C. Pinpoint D. Extra facet
A
Feather
19
Q
Gravity sorting separates diamonds from A. river gravels. B. lighter materials. C. heavier materials. D. indicator minerals.
A
lighter materials.
20
Q
The flashes of color you see in a polished diamond are called A. fire. B. brilliance. C. dispersion. D. scintillation.
A
fire.
21
Q
The devices that grip and hold a diamond for polishing are known as the A. dop and tang. B. tang and stay. C. lap and wheel. D. kerf and sharp.
A
dop and tang.
22
Q
A commitment to reserve a portion of the resources derived from any country for the economic development of that country is called A. integration. B. beneficiation. C. Best Practices. D. the Kimberley Process.
A
beneficiation.
23
Q
Variations in lighting and surroundings can affect a diamond’s A. RI. B. SG. C. luster. D. appearance.
A
appearance.
24
Q
To help determine crystal directions, diamond cutters look for A. kerfs. B. needles. C. growth marks. D. included crystals.
A
growth marks.
25
A masterstone graded as whole grade represents the
A. middle of a color grade’s range.
B. least amount of color possible in that grade’s range.
C. consensus of what the trade believes that color to be. D. greatest amount of color possible in that grade’s range.
least amount of color possible in that grade’s range.
26
De Beers requires its sightholders to have an excellent reputation in the industry and
A. a history of advertising extensively.
B. the ability to cut various types of rough.
C. ownership of a large chain of retail stores.
D. the financial strength to make large purchase commitments.
the financial strength to make large purchase commitments.
27
```
In order to exit a diamond, light must strike an inner surface
A. at a facet junction.
B. inside the critical angle.
C. outside the critical angle.
D. nearly parallel to the surface.
```
inside the critical angle.
28
On a plot, drawing a characteristic only in green indicates that it’s
A. a blemish.
B. part of a mounting.
C. a surface-reaching inclusion.
D. an inclusion totally enclosed within the stone.
a blemish.
29
```
Lower half facet length is expressed as a percentage of the
A. girdle-to-culet distance.
B. table-to-culet distance.
C. girdle-to-girdle distance.
D. lower half facet-to-culet distance.
```
girdle-to-culet distance.
30
```
De Beers became a privately owned company in
A. May 2001.
B. June 2003.
C. May 2005.
D. December 2007.
```
May 2001.
31
The term “diamond simulant”
A. includes only manmade stones.
B. means the same as synthetic diamond.
C. refers to a stone with at least one property that’s the same as diamond.
D. refers to a stone that looks like a diamond but has different optical, physical, and chemical properties.
refers to a stone that looks like a diamond but has different optical, physical, and chemical properties.
32
```
The diamond industry program designed to ensure that diamonds do not fund civil con- flict or terrorism is called
A. integration.
B. beneficiation.
C. Best Practices.
D. the Kimberley Process.
```
the Kimberley Process.
33
```
Diamonds were delivered to the earth’s surface as recently as
A. 20 billion years ago.
B. 20 million years ago.
C. 1 million years ago.
D. 10,000 years ago.
```
20 million years ago.
34
```
Scientists succeeded in producing synthetic industrial diamonds for the first time in the
A. 1800s.
B. 1940s.
C. 1950s.
D. 1990s.
```
1950s.
35
```
One factor used to determine the clarity grade of a diamond is an inclusion’s
A. shape.
B. texture.
C. contour.
D. location.
```
location.
36
VS1 and VS2 stones would be expected to have
A. minor included crystals and feathers.
B. inclusions that might threaten durability.
C. minute inclusions and insignificant blemishes.
D. a few scattered pinpoints and light surface graining.
minor included crystals and feathers.
37
Most diamonds have some symmetry variations
A. that affect the value of the stone.
B. but they rarely affect appearance.
C. that appear both obvious and distracting.
D. but they don’t need to be evaluated when grading.
but they rarely affect appearance.
38
```
The basic causes of a diamond’s color are its crystal structure and
A. refractive index.
B. absorption index.
C. strength of saturation.
D. chemical composition.
```
chemical composition.
39
```
By 2004, more than 90 percent of manufacturing for the diamond market was done in
A. India.
B. Israel.
C. China.
D. South Africa.
```
India.
40
Published wholesale diamond price lists are
A. sponsored by De Beers.
B. valid for London and Antwerp only.
C. accurate reports of prices in most wholesale markets.
D. estimates of wholesale prices in a given market at a certain time.
estimates of wholesale prices in a given market at a certain time.
41
When you color grade a mounted diamond,
A. always remove it from the mounting.
B. you have to use mounted masterstones.
C. tilt the mounting and estimate color through a bezel facet.
D. hold its table beside the masterstone’s table without letting the stones touch.
hold its table beside the masterstone’s table without letting the stones touch.
42
```
A scoop is useful for
A. sorting diamonds by color.
B. sorting diamonds by weight.
C. picking up groups of small gems.
D. measuring the diameters of small diamonds.
```
picking up groups of small gems.
43
```
A mounting makes it impossible to
A. appraise a diamond.
B. accurately weigh a diamond.
C. estimate a diamond’s proportions.
D. locate a diamond’s clarity characteristics.
```
accurately weigh a diamond.
44
```
A group of gems that’s packaged together for sale or storage is called a
A. parcel.
B. sight box.
C. matched set.
D. consignment.
```
parcel.
45
```
Inclusions are usually most visible when they’re located
A. below the girdle.
B. on the girdle plane.
C. under the crown facets.
D. directly under the table.
```
directly under the table.
46
```
A clarity characteristic confined to the surface of a polished gemstone is called a(n)
A. blemish.
B. inclusion.
C. growth mark.
D. surface feature.
```
blemish.
47
```
The most common fancy diamond color is
A. pink.
B. green.
C. brown.
D. orange.
```
brown.
48
```
Vast quantities of small, inexpensive diamonds suitable for low-cost, mass-market jewelry are mined in
A. India.
B. Russia.
C. Canada.
D. Australia.
```
Australia.
49
On an emerald-cut diamond, very narrow corners should be noted under
A. finish, as a polishing detail.
B. finish, as a symmetry variation.
C. proportions, as a shape-appeal factor.
D. proportions, as a length-to-width ratio variation.
proportions, as a shape-appeal factor.
50
```
The soft, diamond-bearing material near the surface of a diamond field was named
A. blueground.
B. easyground.
C. yellowground.
D. shallowground.
```
yellowground.
51
```
Calculate the estimated weight of a round brilliant with the following dimensions:
Average Diameter: 7.25 mm
Depth: 5.45 mm
Girdle Thickness: Very Thick
A. 1.83 cts.
B. 1.85 cts.
C. 1.88 cts.
D. 2.05 cts.
```
1.83 cts.
52
```
The care that goes into the fashioning of a polished diamond, as confirmed by its finish, is its
A. cut.
B. shape.
C. polish.
D. craftsmanship.
```
craftsmanship.
53
```
When using the bowing method, star facets that reach one-third of the way toward the girdle make the lines appear
A. straight.
B. irregular.
C. to bow in.
D. to bow out.
```
to bow out.
54
Grease on the pavilion of a diamond results in
A. more fire.
B. greater brilliance.
C. a smaller critical angle.
D. more light leakage through the pavilion.
more light leakage through the pavilion.
55
```
The most commonly observed color of fluorescence in gem diamond is
A. blue.
B. pink.
C. green.
D. yellow.
```
blue.
56
```
An included diamond crystal that extends to the surface of a fashioned diamond is called a
A. pit.
B. chip.
C. knot.
D. laser drill-hole.
```
knot.
57
```
A diamond imitation that’s foilbacked or composed of colorless lead-glass might be called a
A. zircon.
B. doublet.
C. synthetic.
D. rhinestone.
```
rhinestone.
58
The origin of a diamond’s color
A. can be determined using a DiamondSure.
B. cannot be determined for most diamonds.
C. should usually be determined by a gemological laboratory.
D. can be easily determined with standard gemological equipment.
should usually be determined by a gemological laboratory.
59
The most widely accepted lighting for color-grading diamonds is
A. darkfield.
B. ultraviolet.
C. a balance of darkfield and ultraviolet.
D. balanced, daylight-equivalent fluorescent light.
balanced, daylight-equivalent fluorescent light.
60
```
A notch scratched into diamond rough to prepare it for cleaving is called a
A. tang.
B. kerf.
C. scaife.
D. cleavage.
```
kerf.
61
```
Diamond and graphite are both made of
A. carbon.
B. helium.
C. oxygen.
D. nitrogen.
```
carbon.
62
```
Most diamonds from Australia are
A. large, but of poor color.
B. large and near-colorless.
C. small and poor in quality.
D. small, but of good quality.
```
small and poor in quality.
63
The South African diamond rush was sparked by
A. the arrival of Cecil Rhodes.
B. political changes in Great Britain.
C. reduced supply of Indian diamonds.
D. the discovery of the Star of South Africa.
the discovery of the Star of South Africa.
64
A profitable mine
A. is close to a source of water.
B. has a high percentage of microdiamonds.
C. meets governmental and environmental regulations.
D. produces diamonds whose value is higher than the mine’s operating costs.
produces diamonds whose value is higher than the mine’s operating costs.
65
```
Excessive pavilion bulge on emerald cuts results in
A. excess weight.
B. increased beauty.
C. fewer setting problems.
D. unattractive length-to-width ratio.
```
excess weight.
66
The rotary saw contributed to the diamond-cutting industry by
A. preventing burned facets.
B. allowing for easier cutting of exotic shapes.
C. allowing for greater weight retention from rough.
D. making it easier to cut through knots and crystals.
allowing for greater weight retention from rough.
67
```
A term used to describe any break within a diamond is
A. chip.
B. bruise.
C. feather.
D. abrasion.
```
feather.
68
```
African diamonds are recovered from
A. pipe deposits only.
B. alluvial deposits only.
C. marine deposits only.
D. pipe, alluvial, and marine deposits.
```
pipe, alluvial, and marine deposits.
69
```
Calculate the total depth percentage of a diamond with the following dimensions:
Depth: 4.70 mm
Average girdle diameter: 6.54 mm
A. 71.0 percent
B. 71.9 percent
C. 72.0 percent
D. 72.1 percent
```
71.9 percent
70
```
Some diamond simulants display “see-through” because, compared to diamond, they
A. display less fire.
B. have lower hardness.
C. can’t be polished as well.
D. have much larger critical angles.
```
have much larger critical angles.
71
```
If a diamond has a slight tint in the face-down position and appears colorless in the face- up position, its estimated color grade would be
A. D, E, or F.
B. G,H,I,orJ.
C. K,L,orM.
D. N to Z.
```
G,H,I,orJ.
72
```
The size of a finished gem depends greatly upon the rough diamond’s
A. color.
B. shape.
C. country of origin.
D. optical properties.
```
shape.
73
In the diamond trade, the word “specials” refers to
A. annual diamond sales events.
B. parcels of 5-ct. to 8-ct. rough.
C. diamond rough over 10.80 cts.
D. discounted selections of rough diamonds.
diamond rough over 10.80 cts.
74
```
Before the discovery of South Africa’s diamond deposits, the world’s two major producers were India and
A. Brazil.
B. Russia.
C. Australia.
D. Venezuela.
```
Brazil.
75
A bourse is a(n)
A. agreement to buy on credit.
B. diamond buying and selling club.
C. financial arrangement between miners and cutters.
D. disclosure that a parcel of diamonds has been treated.
diamond buying and selling club.
76
Crystal shape is an important factor in the evaluation of rough because
A. it influences the clarity grade.
B. it often affects color and clarity.
C. some crystal shapes are much softer than others.
D. it affects the amount of weight retained after cutting
it affects the amount of weight retained after cutting
77
```
A diamond’s clarity and color grades indicate its
A. quality.
B. popularity.
C. retail price.
D. wholesale price.
```
quality.
78
```
The proportions that play the biggest role in determining a round brilliant diamond’s brightness are table percentage, crown angle, and
A. culet size.
B. pavilion angle.
C. crown height percentage.
D. girdle thickness percentage.
```
pavilion angle.
79
```
The concentration of diamonds within a pipe is called
A. drift.
B. ore grade.
C. overburden.
D. rough grade.
```
ore grade.
80
```
When using the ratio method for estimating table percentage, a 1:1 1⁄4 ratio indicates a table of approximately
A. 54 percent.
B. 60 percent.
C. 65 percent.
D. 69 percent.
```
60 percent.
81
```
In most cases, the easier it is to see a clarity characteristic, the
A. less durable the stone.
B. lower the clarity grade.
C. more durable the stone.
D. higher the clarity grade.
```
lower the clarity grade.
82
```
The strongest of all atomic bonds are called
A. shells.
B. covalent.
C. magnetic.
D. electrons.
```
covalent.
83
```
Diamonds are more concentrated in
A. marine deposits.
B. primary deposits.
C. volcanic deposits.
D. mountain deposits.
```
marine deposits.
84
```
An example of a blemish is a
A. chip.
B. knot.
C. bruise.
D. natural.
```
natural.
85
```
The diamond term glassie refers to
A. an aggregate mass.
B. a well-formed octahedral crystal.
C. a noticeably rounded hexoctahedron.
D. a macle with an abundance of trigons.
```
a well-formed octahedral crystal.
86
```
To calculate the table percentage of a fancy shape, divide the table size by the stone’s
A. width.
B. length.
C. average diameter.
D. diagonal measurement.
```
width.
87
```
The easiest way to separate diamond from zircon is by checking for
A. doubling.
B. see-through.
C. specific gravity.
D. refractive index.
```
doubling.
88
```
A gem with triangular and kite-shaped facets that radiate from its center toward its girdle is called a
A. step cut.
B. mixed cut.
C. French cut.
D. brilliant cut.
```
brilliant cut.
89
What is the correct adjustment factor to use when estimating the weight of an emerald-cut diamond with the following dimensions?
Length: 8.40 mm Width: 5.59 mm Depth: 2.85 mm
A. 0.0080
B. 0.0092
C. 0.0100
D. 0.0106
0.0092
90
```
Annealed diamond color can change if it’s exposed to
A. ultraviolet rays in sunlight.
B. heat during routine repairs.
C. chlorine in swimming pools.
D. ammonia in cleaning solutions.
```
heat during routine repairs.
91
```
The crystal planes most suitable for cleaving a diamond are the
A. cubic planes.
B. octahedral planes.
C. dodecahedral planes.
D. trisoctahedral planes.
```
octahedral planes.
92
```
Atoms in a gem that aren’t part of its essential chemical composition are called
A. trace elements.
B. foreign elements.
C. distortion impurities.
D. irregularity elements.
```
trace elements.
93
```
Trade terms that describe diamond color
A. can be misleading.
B. are accurate for certain stones.
C. are usually very clearly defined.
D. are based on the names of famous diamantaires.
```
can be misleading.
94
```
Calculate an estimated girdle thickness percentage for the following stone:
Total depth percentage: 62.8%
Crown height percentage: 15.5%
Pavilion depth percentage: 45.5%
A. 1.0%
B. 1.5%
C. 2.0%
D. 2.5%
```
2.0%
95
```
The correct conditions for diamond formation exist under
A. cratons.
B. volcanic ash.
C. oceanic crust.
D. large mountain ranges.
```
cratons.
96
```
Subduction occurs when
A. volcanoes erupt.
B. mountains collide.
C. tidal waves sweep over landmasses.
D. two of the earth’s crustal plates collide.
```
two of the earth’s crustal plates collide.
97
The main reason that dealers charge less when diamonds are paid for immediately is that
A. it simplifies their bookkeeping.
B. it reduces the likelihood of returned goods.
C. dealers like to boast of their monthly sales figures.
D. dealers usually borrow money to finance their own purchases.
dealers usually borrow money to finance their own purchases.
98
```
A mine’s potential profitability depends in part on
A. its ore grade.
B. its location on a craton.
C. having a small, compact pipe.
D. a good kimberlite-to-lamproite ratio.
```
its ore grade.
99
The use of synthetic diamonds in jewelry
A. is limited by high production costs.
B. makes up a substantial portion of the market.
C. is limited to fancy-colored melee, which is mostly synthetic.
D. is currently impossible because the synthetics are too highly included.
is limited by high production costs.
100
```
Which of the following makes a diamond unsuitable for a masterstone set?
A. SI1 clarity
B. Yellowish bodycolor
C. Very strong fluorescence
D. About 43 percent pavilion depth
```
Very strong fluorescence
101
An extremely thick girdle
A. makes a stone easier to set.
B. creates an unattractive fish-eye effect.
C. reduces a stone’s durability during normal wear.
D. adds weight without contributing to the stone’s appearance.
adds weight without contributing to the stone’s appearance.
102
```
Princess cuts are popular in jewelry designs that call for
A. curved lines.
B. pavé settings.
C. an antique look.
D. channel settings.
```
channel settings.
103
Large, high-quality diamonds are
A. sorted rather than graded.
B. usually graded in their mountings.
C. graded with a quick look under a loupe.
D. graded much more thoroughly than small, low-quality ones.
graded much more thoroughly than small, low-quality ones.
104
```
The crown angle is the angle formed by the girdle plane and the
A. table.
B. star facets.
C. bezel facets.
D. upper half facets.
```
bezel facets.
105
Diamond’s supreme hardness and durability are
A. due to diamond’s rarity.
B. a result of the conditions under which it formed.
C. surpassed by laboratory-grown diamond substitutes.
D. a result of millions of years of battering by the forces of nature.
a result of the conditions under which it formed.
106
```
Which diamond simulant shows noticeable doubling and strong fire?
A. CZ
B. Zircon
C. Synthetic rutile
D. Strontium titanate
```
Synthetic rutile
107
```
A surface indentation with tiny, root-like feathers penetrating the stone is called a
A. knot.
B. cavity.
C. bruise.
D. natural.
```
bruise.
108
```
To find the crown height percentage, you must know the crown angle and the
A. table percentage.
B. average girdle diameter.
C. pavilion depth percentage.
D. girdle thickness percentage.
```
table percentage.
109
```
A loose brown diamond should be color-graded
A. using a 10⨉ loupe.
B. as a range of colors.
C. as a top light brown.
D. against a yellow masterstone set.
```
against a yellow masterstone set.
110
```
What is the crown height percentage of a diamond with a crown angle of 32 degrees and a 60 percent table?
A. 11.5 percent
B. 12.5 percent
C. 12.8 percent
D. 13.7 percent
```
12.5 percent
111
```
The smallest group of atoms with a characteristic chemical composition and the basic crystal structure of a mineral is called a(n)
A. atom.
B. unit cell.
C. tetrahedron.
D. building block.
```
unit cell.
112
```
A city, region, or country with a large number of gemstone manufacturers is called a
A. trade center.
B. market center.
C. cutting center.
D. business center.
```
cutting center.
113
```
The involvement of a business or industry in all aspects of its product’s market is called
A. best practices.
B. blanket marketing.
C. electronic retailing.
D. vertical integration.
```
vertical integration.
114
```
A knowledgeable, experienced, and successful diamond dealer or manufacturer is called a(n)
A. sorter.
B. manager.
C. auctioneer.
D. diamantaire.
```
diamantaire.
115
When estimating the weight of very small diamonds, graders
A. often use templates.
B. don’t adjust for proportion variations.
C. use the same techniques as for larger diamonds.
D. must use more adjustment factors than for larger stones.
often use templates.
116
```
A “paper-worn” diamond is one that has
A. naturals.
B. abrasions.
C. extra facets.
D. a bearded girdle.
```
abrasions.
117
```
A diamond cutter’s main objectives are to produce an attractive finished diamond and
A. maximize profits.
B. cut round brilliants.
C. cut ideal proportions.
D. retain as little weight as possible.
```
maximize profits.
118
```
The difference between the RI values of specific violet and red wavelengths of visible light for a given material is its
A. fire.
B. dispersion.
C. critical angle.
D. transmission value.
```
dispersion.
119
```
A rapid and efficient way to sort large numbers of small, round diamonds is to use a(n)
A. template.
B. sieve set.
C. electronic scale.
D. millimeter gauge.
```
sieve set.
120
```
If a diamond weighs 1.83 cts. and its price is $13,725, what is its per-carat price?
A. $750
B. $7,500
C. $13,725
D. $25,116
```
$7,500
121
```
Subtle color differences are usually more visible when seen
A. face-up.
B. through the pavilion.
C. through the bezel facets.
D. through the crown facets.
```
through the pavilion.
122
```
Which of the following is classified as an inclusion?
A. Nick
B. Chip
C. Scratch
D. Rough girdle
```
Chip
123
Reputable gemological laboratories don’t grade mounted diamonds because
A. it takes too much time.
B. their insurance policies don’t permit it.
C. mountings hide details of clarity and cut.
D. the designs of the mountings might influence their decisions.
mountings hide details of clarity and cut.
124
```
What is the specific gravity of gem-quality diamond?
A. 1.00
B. 2.17
C. 3.52
D. 4.01
```
3.52
125
```
The slightly curved, central areas on the sides of some brilliant fancy cuts are called
A. lobes.
B. bezels.
C. bellies.
D. centers.
```
bellies.
126
In diamonds, cleavage is caused by
A. variations in density.
B. irregular atomic structure.
C. octahedrons with points that are easily broken.
D. relatively wide spaces between some atomic planes.
relatively wide spaces between some atomic planes.
127
Inclusions or blemishes that establish the clarity grade of a diamond are collectively called
grade-setting characteristics.
128
Once diamond deposits are located, mining companies
A. begin extracting the diamonds.
B. recover the cost of exploration within the first year.
C. are exempt from taxes and environmental regulations.
D. must spend additional time and money to evaluate and develop them.
must spend additional time and money to evaluate and develop them.
129
```
A reflector is the result of the inclusion’s
A. size.
B. relief.
C. shape.
D. position.
```
position.
130
```
The shift in emphasis from alluvial to primary diamond mining was due to
A. improved technology.
B. environmental concerns.
C. depletion of secondary sources.
D. political and governmental pressures.
```
improved technology.
131
```
Diamonds described as “thirds” typically range in weight from
A. 0.25 to 0.30 ct.
B. 0.28 to 0.30 ct.
C. 0.30 to 0.33 ct.
D. 0.30 to 0.37 ct.
```
0.30 to 0.37 ct.
132
```
Which of the following pavilion depth percentages would most likely cause the girdle reflection to be visible face-up through the table?
A. 37.0%
B. 42.0%
C. 45.0%
D. 48.0%
```
37.0%
133
```
The inclusion called bearding consists of tiny
A. knots.
B. needles.
C. feathers.
D. grain lines.
```
feathers.
134
```
An improvable is a diamond that can be repolished to improve its clarity
A. to Flawless.
B. from I3 to SI2.
C. to VVS1 or VVS2.
D. to Internally Flawless.
```
to VVS1 or VVS2.
135
To see a diamond’s clarity characteristics that might be hidden by prongs,
A. use reflections.
B. use soft, diffused lighting.
C. gently bend the prongs out of the way.
D. look at the diamond in the face-up position.
use reflections.
136
```
Diamonds with minute inclusions that are difficult for even a skilled grader to see under 10X are classified
A. IF.
B. SI1 or SI2.
C. VS1 or VS2.
D. VVS1 or VVS2.
```
VVS1 or VVS2.
137
The more an inclusion differs in color from its host diamond,
A. the less obvious it is.
B. the more obvious it is.
C. the more valuable the diamond is.
D. the higher the diamond’s clarity grade.
the more obvious it is.
138
```
A solid mineral body enclosed within a diamond (or other gem) is
A. a knot.
B. a natural.
C. internal graining.
D. an included crystal.
```
an included crystal.
139
```
In the cutting sequence, the crown and pavilion mains are polished by the
A. bruter.
B. blocker.
C. finisher.
D. brillianteer.
```
blocker.
140
```
Diamond deposits found at the ocean’s shore are
A. marine deposits.
B. primary deposits.
C. industrial deposits.
D. shoreline deposits.
```
marine deposits.
141
A diamond’s recut style is largely determined by
A. its original cut.
B. the cutter’s favorite style.
C. which style is most in demand.
D. how many inclusions the cutter can remove.
its original cut.
142
```
Diamonds outside the normal color range are graded
A. face-up.
B. face-down.
C. through the girdle.
D. from the pavilion view.
```
face-up.
143
```
The program adopted by De Beers in 2007 to answer critics and resolve shortcomings of its SOC program is called
A. Beneficiation.
B. Kimberley Practices.
C. Supplier of Choice 2.
D. Best Practices Principles.
```
Supplier of Choice 2.
144
```
Which of the following is part of an evaluation of symmetry?
A. Scratch
B. Natural
C. Rough girdle
D. Laser manufacturing remnant
```
Natural
145
```
In South Africa, a new mining charter that designates the people of the country as the owners of its mineral resources is a result of
A. apartheid.
B. beneficiation.
C. vertical integration.
D. Black Economic Empowerment.
```
Black Economic Empowerment.
146
```
Which of the following is a natural gem?
A. YAG
B. GGG
C. Zircon
D. Strontium titanate
```
Zircon
147
In 2000, De Beers altered its consumer advertising by
A. doubling its advertising budget.
B. changing its advertising agency.
C. introducing the “Forevermark” logo.
D. discouraging dealers from doing their own advertising.
introducing the “Forevermark” logo.
148
```
If a diamond’s minimum girdle diameter is 4.62 mm and its maximum girdle diameter is 4.65 mm, then its average girdle diameter is
A. 4.625 mm.
B. 4.630 mm.
C. 4.635 mm.
D. 4.640 mm.
```
4.635 mm.
149
When color-grading with masterstones, you should
A. compare the unknown only on the left side of the masterstone.
B. compare the unknown only on the right side of the masterstone.
C. move the unknown to compare it on both sides of the masterstone.
D. move the masterstone to compare it on both sides of the unknown stone.
move the unknown to compare it on both sides of the masterstone.
150
A grooved, white, non-reflective tray is used to
A. match sets of stones.
B. clarity grade VVS and VS stones.
C. hold stones in place while measuring.
D. prepare stones for ultrasonic cleaning.
match sets of stones.
151
```
Dealers often sort melee by size using
A. scales.
B. sieves.
C. templates.
D. millimeter gauges.
```
sieves.
152
```
Diamonds classified as cuttable can be 100 times more valuable than
A. marine diamonds.
B. alluvial diamonds.
C. industrial diamonds.
D. gem-quality diamonds.
```
industrial diamonds.
153
```
The relative size, arrangement, and contrast of bright and dark areas that result from a diamond’s internal and external reflections is called
A. pattern.
B. sparkle.
C. refraction.
D. transmission.
```
pattern.
154
De Beers Consolidated Mines Ltd. was named after
A. the president of South Africa.
B. the man who found the Eureka Diamond.
C. the district where the Star of South Africa was found.
D. the owners of a farm where one of the first diamond rushes took place.
the owners of a farm where one of the first diamond rushes took place.
155
```
The easiest way to separate diamond from synthetic cubic zirconia is by checking for
A. fire.
B. doubling.
C. thermal conductivity.
D. Mohs scale hardness.
```
thermal conductivity.
156
```
A stone formed by cementing two separate pieces of material together is called a
A. doublet.
B. synthetic.
C. assembly.
D. construction.
```
doublet.
157
```
The emission of visible light by a material when it’s exposed to ultraviolet radiation is called
A. UV light.
B. atomic glow.
C. fluorescence.
D. spectral emission.
```
fluorescence.
158
```
The purpose of the culet facet is to
A. prevent chipping.
B. improve symmetry.
C. maximize brilliance.
D. maximize light leakage.
```
prevent chipping.
159
```
Which of the following appears only on fancy cuts?
A. Culet
B. Girdle
C. Keel line
D. Upper half facets
```
Keel line
160
```
A diamond’s physical shape, including its proportions and durability, determined by decisions made during the fashioning process, is its
A. finish.
B. polish.
C. design.
D. brilliance.
```
design.
161
```
Type I diamonds contain
A. boron.
B. helium.
C. oxygen.
D. nitrogen.
```
nitrogen.
162
Diamond rough suitable for use in tools, drills, and abrasives is
A. cuttable quality.
B. industrial quality.
C. primarily from marine deposits.
D. a byproduct of the exploration process.
industrial quality.
163
```
Colorless diamonds are more valuable than others in the normal color range because they
A. do not fade.
B. are more rare.
C. have fewer inclusions.
D. look better in yellow gold mountings.
```
are more rare.
164
```
Which diamond mine’s huge production influenced the world market in the late 1980s?
A. Ekati
B. Argyle
C. Jwaneng
D. Kimberley
```
Argyle
165
Which one of the following is typical of the UV fluorescence of synthetic diamonds?
A. Strong blue under both longwave and shortwave.
B. Blue under longwave and weak yellow under shortwave.
C. Strong yellow under longwave and none under shortwave.
D. Yellow to greenish yellow under both longwave and shortwave.
Yellow to greenish yellow under both longwave and shortwave.
166
A noticeable “oily” appearance seen in some diamonds is usually the result of
A. very strong fluorescence.
B. a failed attempt to bleach the color.
C. a poorly applied colored lacquer coating.
D. radioactive residues from an artificial coloring process.
very strong fluorescence.
167
```
Another name for the cubic crystal system is
A. isotropic.
B. isometric.
C. anisotropic.
D. isomorphous.
```
isometric.
168
```
Dirt and clay are washed from diamond-bearing ore by
A. cleaners.
B. agitators.
C. scrubbers.
D. grease belts.
```
scrubbers.
169
A feather that reaches a bezel surface as well as the surface of the pavilion main directly under that bezel
A. does not need to be plotted.
B. should be plotted only on the crown diagram.
C. should be plotted only on the pavilion diagram.
D. should be plotted on both the crown and pavilion diagrams.
should be plotted on both the crown and pavilion diagrams.
170
```
A naturally occurring, inorganic substance with a characteristic chemical composition and usually a characteristic crystal structure is known as a
A. rock.
B. crystal.
C. variety.
D. mineral.
```
mineral.
171
```
The ultimate recutting consideration is
A. how badly the stone is damaged.
B. how much the color can be improved.
C. how much the clarity can be improved.
D. the potential value of the finished diamond.
```
the potential value of the finished diamond.
172
```
A transparent measuring device divided into millimeters and tenths of a millimeter, used to measure a diamond’s table, is called a
A. ruler.
B. table gauge.
C. micrometer.
D. tape measure.
```
table gauge.
173
```
Which of the following requires the greatest adjustment to estimated weight?
A. Thick girdle
B. Long star facets
C. Shallow pavilion
D. Steep crown angles
```
Thick girdle
174
```
The Argyle mine is famous for diamonds that are
A. pink.
B. blue.
C. large.
D. colorless.
```
pink.
175
```
Which of the following diamond colors would be the most valuable, all other factors being equal?
A. Red
B. Gray
C. Brown
D. Deep yellow
```
Red
176
Accurate weight estimation of a mounted diamond requires
A. a computer imaging system.
B. very little skill or experience.
C. careful measurement with a table gauge.
D. making adjustments for proportion variations.
making adjustments for proportion variations.
177
```
The angle of incidence always equals the
A. RI.
B. angle of reflection.
C. dispersion of diamond.
D. critical angle of diamond.
```
angle of reflection.
178
```
Who established De Beers Consolidated Mines Ltd. in 1888?
A. Cecil Rhodes
B. Barney Barnato
C. Harry Oppenheimer
D. A Dutch farmer named De Beers
```
Cecil Rhodes
179
```
A portion of the rough’s original surface, or skin, that dips below the polished diamond’s surface is called a(n)
A. indented natural.
B. internal graining.
C. colored grain center.
D. laser manufacturing remnant.
```
indented natural.
180
```
The passage of light into or through a material is called
A. reflection.
B. dispersion.
C. absorption.
D. transmission.
```
transmission.
181
```
If a diamond weighs 0.76 ct. and the per-carat price is $4,100, how much does the diamond cost?
A. $3,116
B. $3,120
C. $4,000
D. $5,395
```
$3,116
182
```
Businesses that sell to consumers via television or computer are called
A. electronic retailers.
B. suppliers of choice.
C. digital diamond dealers.
D. vertically integrated marketers.
```
electronic retailers.
183
```
In a good-quality pavé-set ring, the diamonds will have matching girdle diameters, colors, and
A. weights.
B. table sizes.
C. brand names.
D. clarity grades.
```
table sizes.
184
Chambering and block caving are methods used in
A. mining diamond pipes.
B. mining alluvial deposits.
C. testing the productivity of diamond pipes.
D. testing the productivity of alluvial deposits.
mining diamond pipes.
185
```
The habit of gem-quality diamond is the
A. cube.
B. octahedron.
C. dodecahedron.
D. hexoctahedron.
```
octahedron.
186
```
Diamond prices on wholesale price lists
A. are not negotiable.
B. reflect a worldwide consensus.
C. are available free on the Internet.
D. depend on the market conditions that exist when the lists are published.
```
depend on the market conditions that exist when the lists are published.
187
```
Culet size should be considered when determining
A. polish.
B. clarity.
C. symmetry.
D. pavilion depth percentage.
```
pavilion depth percentage.
188
```
The first authenticated diamond discovered in South Africa is named the
A. Eureka.
B. Cullinan.
C. De Beers.
D. Star of Africa.
```
Eureka.
189
```
As a diamond’s pavilion gets deeper, its table reflection becomes
A. larger.
B. lighter.
C. smaller.
D. more difficult to see.
```
larger.
190
```
During emplacement, if diamonds are exposed to high temperature along with decreased pressure for a long period, they will
A. melt.
B. explode.
C. vaporize.
D. convert to graphite.
```
convert to graphite.
191
```
A sorting pad is a
A. weighing device.
B. type of cleaning apparatus.
C. grooved, non-reflective plastic tray.
D. clean and convenient paper surface for examining gems.
```
clean and convenient paper surface for examining gems.
192
Dense media separation is based on the fact that
A. diamonds stick to grease.
B. most diamonds fluoresce when X-rayed.
C. diamonds float to the top of a mix of crushed ore.
D. diamonds sink to the bottom of a mix of crushed ore.
diamonds sink to the bottom of a mix of crushed ore.
193
```
On a marquise-shaped, brilliant-cut diamond, pavilion-angle variations can result in
A. a fisheye.
B. a bow-tie.
C. pavilion bulge.
D. dark areas under the points.
```
a bow-tie.
194
```
Diamond sources started appearing in South Africa during the
A. 1740s.
B. 1820s.
C. 1860s.
D. 1910s.
```
1860s.
195
```
If a diamond’s pavilion depth percentage is 39.0 percent with no culet facet, its pavilion angle is approximately
A. 37.8 degree
B. 38.0 degree
C. 38.4 degree
D. 38.8 degree
```
38.0 degree
196
```
The easiest way to separate diamond from synthetic moissanite is by checking for
A. doubling.
B. brilliance.
C. refractive index.
D. thermal conductivity.
```
doubling.
197
Laser drill-holes
A. usually reduce the clarity grade.
B. don’t need to be disclosed to customers.
C. become permanent clarity characteristics.
D. aren’t permanent, so major labs won’t grade them.
become permanent clarity characteristics.
198
```
If a diamond’s culet is too large, it will look like
A. a small cavity.
B. an indented natural.
C. a fuzzy, white speck.
D. a black spot under the table.
```
a black spot under the table.
199
```
A horizontal tunnel drilled through a diamond pipe is called a
A. path.
B. drift.
C. shaft.
D. channel.
```
drift.
200
```
To focus their search for diamond deposits, geologists look for
A. river gravels.
B. trace elements.
C. indicator minerals.
D. small grains of graphite.
```
indicator minerals.
201
```
The thermal diamond tester helps separate diamond from most simulants because of diamond’s excellent ability to
A. reflect light.
B. refract light.
C. conduct heat.
D. conduct electricity.
```
conduct heat
202
```
Shortly before the discovery of the South African deposits, the world’s major diamond producer was
A. India.
B. Brazil.
C. Russia.
D. Canada.
```
Brazil.
203
```
Which of the following is not a diamond inclusion?
A. Cloud
B. Feather
C. Gas bubble
D. Included crystal
```
Gas bubble
204
```
If a diamond’s total depth percentage is 51.0 percent, its cut grade will be
A. Superior or Excellent.
B. Excellent or Very Good.
C. Very Good or Good.
D. Fair or Poor.
```
Fair or Poor.
205
```
The change in speed and possible change in direction of light as it travels from one material to another is called
A. reflection.
B. refraction.
C. dispersion.
D. scintillation.
```
refraction.
206
```
Most synthetic gem-quality diamonds are
A. blue.
B. pink.
C. colorless.
D. yellow or brown.
```
yellow or brown.
207
```
The basic face-up color of a colored diamond is known as its
A. real color.
B. actual color.
C. apparent color.
D. characteristic color.
```
characteristic color.
208
The first step in exploring for diamonds is to
A. collect bulk samples of ore.
B. search for ancient volcanoes.
C. look for the oldest parts of the earth’s crust.
D. examine river gravels for indicator minerals.
look for the oldest parts of the earth’s crust.
209
Wholesale price lists are usually organized according to
A. recent auction prices.
B. traditional jewelry-buying seasons.
C. specific combinations of the Four Cs.
D. sales at major diamond-trading centers.
specific combinations of the Four Cs.
210
```
The cast-iron disc on which a diamond is polished is called a
A. dop.
B. kerf.
C. tang.
D. scaife.
```
scaife.
211
```
The path diamonds followed from mine to consumer was called the
A. retail route.
B. sight system.
C. diamond track.
D. diamond pipeline.
```
diamond pipeline
212
```
The largest percentage of world diamond production (by weight) is mined in
A. Brazil.
B. Angola.
C. Australia.
D. Indonesia.
```
Australia.
213
```
Removal of mineral-bearing ore from a surface excavation is called
A. drift mining.
B. open-pit mining.
C. open-air mining.
D. original-source mining.
```
open-pit mining.
214
```
Calculate the length-to-width ratio of the following pear shape:
Length 7.51 mm Width 5.19 mm
A. 1.44:1
B. 1.45:1
C. 1.69:1
D. 1.70:1
```
1.45:1
215
```
A structural defect that influences a gem’s absorption of light is called a(n)
A. color center.
B. lattice strain.
C. impurity center.
D. absorption center.
```
color center.
216
```
Diamond simulants
A. are always manmade.
B. only look like diamonds.
C. are the same as synthetic diamonds.
D. have the same properties as natural diamonds.
```
only look like diamonds.
217
```
The directional properties and structural features of a diamond crystal do not really matter in
A. cleaving.
B. laser sawing.
C. conventional sawing.
D. automated polishing.
```
laser sawing.
218
Most modern diamond-mining operations are
A. done with simple hand tools.
B. small in scale and not very expensive.
C. large in scale and extremely expensive.
D. performed in temperature-controlled environments.
large in scale and extremely expensive.
219
```
The group that united in 1890 to buy and sell all of the output of the major diamond producers, including De Beers, was the
A. French Company.
B. Dutch East India Company.
C. Diamond Trading Company.
D. London Diamond Syndicate.
```
London Diamond Syndicate.
220
```
Diamond is hard and graphite is soft because of the difference in
A. their atoms.
B. their transparency.
C. their chemical formulas.
D. the way their atoms fit together.
```
the way their atoms fit together.
221
```
Blemishes don’t usually affect the clarity grade in diamonds below
A. IF.
B. SI.
C. VS.
D. VVS.
```
IF.
222
```
When you buy an entire parcel, you can expect to pay a
A. lot price.
B. pick price.
C. memo price.
D. consignment price.
```
lot price.
223
The Argyle mine in Australia contributed to
A. an economic slowdown in Australia.
B. the rise of the cutting industry in India.
C. the decline of production in South Africa.
D. the rise of the cutting industry in Australia.
the rise of the cutting industry in India.
224
```
Where on a fancy-cut diamond might multiple facet reflections make it most difficult to detect clarity characteristics?
A. Belly
B. Point
C. Wing
D. Shoulder
```
Point
225
```
A flat, triangular twinned diamond crystal is called a
A. macle.
B. cleavage.
C. splittable.
D. tetrahedron.
```
macle.
226
```
The relative lightness or darkness of a color is called its
A. hue.
B. tone.
C. intensity.
D. saturation.
```
tone.
227
```
Diamond rough suitable for use in jewelry is called
A. cuttable.
B. Grade A.
C. top-quality.
D. jewelry-quality.
```
cuttable.
228
```
The proper environment for diamond formation includes the right temperature, pressure, and
A. molten lava.
B. indicator minerals.
C. the availability of carbon.
D. the presence of trace elements.
```
the availability of carbon.
229
```
The color grade of a diamond that appears darker than the H masterstone but lighter than the I would be
A. G.
B. H.
C. H-I.
D. I.
```
H.
230
```
Calculate the estimated weight of a heart-shaped brilliant with the following dimensions:
Length: 5.58 mm
Width: 5.51 mm
Depth: 3.21 mm
Girdle Thickness: Medium
A. 0.51 ct.
B. 0.55 ct.
C. 0.58 ct.
D. 0.61 ct.
```
0.58 ct.
231
```
The most consistent and dependable sources of diamond grades are
A. appraisers.
B. wholesalers.
C. mining experts.
D. reputable gemological laboratories.
```
reputable gemological laboratories.
232
```
A stone with only a few extra facets on its pavilion that can’t be seen face-up should be graded
A. IF.
B. VS1.
C. VVS1.
D. Flawless.
```
Flawless.
233
```
Most round brilliants have table percentages that range from about
A. 35 to 40 percent.
B. 45 to 50 percent.
C. 55 to 65 percent.
D. 70 to 75 percent.
```
55 to 65 percent.
234
```
A faceting style that replaces the large bezel facets at the points of some diamonds with star and upper half facets is called a
A. star tip.
B. bezel tip.
C. French tip.
D. point facet.
```
French tip.
235
```
The rounded end of a pear-shaped stone is called the
A. lobe.
B. apex.
C. head.
D. wing.
```
head.
236
```
Most of the diamonds mined today come from
A. pipes.
B. beaches.
C. riverbeds.
D. the ocean floor.
```
pipes.
237
```
The appearance of a material’s surface in reflected light is called
A. luster.
B. reflectance.
C. polish quotient.
D. incident light return.
```
luster.
238
```
The higher the optical density of a material, the
A. less it bends light.
B. less it reflects light.
C. more it speeds light up.
D. more it slows light down.
```
more it slows light down.
239
The diamond industry has changed dramatically in recent years because
A. demand for finished diamonds has decreased.
B. the world’s supply of diamond rough has increased.
C. the world’s supply of diamond rough has significantly decreased.
D. environmental regulations have caused many mines to shut down.
the world’s supply of diamond rough has increased.
240
```
Visible light is
A. also called brilliance.
B. the result of dispersion.
C. a form of radiant energy.
D. a type of ultraviolet radiation.
```
a form of radiant energy.
241
An advantage of the face-up method of crown-angle estimation is that it
A. can be used with mounted diamonds.
B. can be used for several cutting styles.
C. can be performed without magnification.
D. is based on a view of the actual crown angle.
can be used with mounted diamonds.
242
```
The designation SI means
A. Slightly Included.
B. Severely Included.
C. Several Inclusions.
D. Somewhat Included.
```
Slightly Included.
243
Which one of the following is used today to safely color-treat diamonds?
A. X-rays
B. Radium compound
C. Ultraviolet radiation
D. High-energy electrons in a linear accelerator
High-energy electrons in a linear accelerator
244
```
Only a small percentage of known diamond deposits are mined because most
A. are not profitable.
B. are too close to populated areas.
C. are too far from populated areas.
D. require expensive government permits.
```
are not profitable.
245
```
The GIA Laboratory uses a Z masterstone to determine fancy
A. blues.
B. pinks.
C. greens.
D. yellows.
```
yellows.
246
Which one of the following is an indication of HPHT treatment?
A. Flash effect
B. Hourglass graining
C. Etched or frosted naturals
D. Color zoning parallel to facet junctions
Etched or frosted naturals
247
```
A wholesaler is someone who
A. sells to retailers.
B. repairs diamond jewelry.
C. grows synthetic diamonds.
D. sells directly to consumers.
```
sells to retailers.
248
```
Scientists have found that diamonds form in two types of rocks, called
A. marble and shale.
B. sandstone and schist.
C. peridotite and eclogite.
D. kimberlite and lamproite.
```
peridotite and eclogite.
249
Color-treating diamonds in a linear accelerator produces
A. distinctive color zoning.
B. blue or blue-green colors.
C. usually green or dark green colors.
D. only shallow penetration of the color.
blue or blue-green colors.
250
Sightholders purchase diamond rough by
A. going directly to the mines.
B. attending invitation-only trading events.
C. selecting from lists sent out by De Beers.
D. contacting other sightholders in their area.
attending invitation-only trading events.
251
```
Before arriving at the earth’s surface, diamonds might remain in the mantle for as long as a few
A. days.
B. hours.
C. hundred years.
D. hundred million years.
```
hundred million years.
252
A round brilliant-cut VVS diamond could have
A. a laser drill-hole.
B. a small feather under the table.
C. an included crystal under a star facet.
D. a small pinpoint under a lower girdle facet.
a small pinpoint under a lower girdle facet.
253
```
Compared to round brilliants, one difference in the color-grading process for fancy-cut diamonds is the
A. type of light.
B. viewing direction.
C. type of magnification.
D. shape of the masterstones.
```
viewing direction.
254
The Diamond Information Center and the Diamond Promotion Service were created to
A. assist in diamond marketing efforts.
B. raise funds for diamond exploration.
C. lobby for increased diamond mining.
D. train diamond cutters and manufacturers.
assist in diamond marketing efforts.
255
```
A diamond with variations in alignment probably also has
A. polish lines.
B. misshapen facets.
C. a low clarity grade.
D. an out-of-round girdle outline.
```
misshapen facets.
256
```
With darkfield illumination, light is directed into the stone from
A. below.
B. above.
C. the side.
D. all directions.
```
the side.
257
```
The person who decides where to mark diamond rough for fashioning is called the
A. bruter.
B. planner.
C. blocker.
D. brillianteer.
```
planner.
258
One of the changes that resulted from De Beers’ strategic review in 1999 was that De Beers
A. stopped advertising diamonds.
B. doubled its advertising budget.
C. discontinued its sightholder program.
D. changed the name of the CSO to the DTC.
changed the name of the CSO to the DTC.
259
```
The Central Selling Organisation was a
A. diamond mining company.
B. major diamond manufacturer.
C. rough diamond distribution agency.
D. diamond industry public relations service.
```
rough diamond distribution agency.
260
```
An early brilliant that has a circular girdle outline is called
A. a table cut.
B. a point cut.
C. an old-mine cut.
D. an old European cut.
```
an old European cut.
261
```
For more than 2,000 years, the only known diamond sources were
A. alluvial.
B. primary.
C. kimberlite pipes.
D. ancient volcanic craters.
```
alluvial.
262
```
The diamonds used as comparison stones for color grading in the normal color range are called
A. D-to-Z sets.
B. color stones.
C. masterstones.
D. color comparators.
```
masterstones
263
```
The chart of weight adjustment factors begins to apply when the overall girdle thickness is rated as
A. thin.
B. thick.
C. medium.
D. slightly thick.
```
slightly thick.
264
A diamond with a thick girdle, steep crown, or deep pavilion represents poor value because
A. it doesn’t look attractive.
B. it can’t be set into a jewelry piece.
C. it appears smaller face-up than its weight suggests.
D. its proportions create durability problems in the polished stone.
it appears smaller face-up than its weight suggests.
265
```
A common method of permanently changing the color of a diamond is
A. coating.
B. irradiating.
C. laser drilling.
D. organic dyeing.
```
irradiating.
266
```
Russia’s significant diamond deposits are in
A. Siberia.
B. Belorussia.
C. the Crimea.
D. the Kaliningrad Oblast.
```
Siberia.
267
```
Solid matter with atoms arranged in a regular, repeating pattern is called a(n)
A. rock.
B. crystal.
C. variety.
D. element.
```
crystal.
268
```
Which of these would disqualify a stone from being graded IF?
A. Scratch
B. Pinpoint
C. Abraded culet
D. Surface grain line
```
Pinpoint
269
```
Type IIb diamonds contain
A. boron.
B. helium.
C. sodium.
D. potassium.
```
boron.
270
```
The number of facets on a single-cut diamond is
A. 7 or 8.
B. 17 or 18.
C. 19 or 20.
D. 57 or 58.
```
17 or 18.
271
```
Annealing irradiated diamonds can produce
A. intense blue.
B. emerald green.
C. D-grade colorless.
D. brown, orange, or yellow.
```
brown, orange, or yellow.
272
```
The cutting style with a flat bottom and a variable number of facets that come to a peak at the top is the
A. rose cut.
B. table cut.
C. point cut.
D. single cut.
```
rose cut.
273
```
Which is the softest crystal direction in diamond?
A. Cubic
B. Octahedral
C. Hexahedral
D. Dodecahedral
```
Dodecahedral
274
A round brilliant diamond’s table size is expressed as
A. excellent, good, or fair.
B. small, medium, or large.
C. a ratio of its depth to its diameter.
D. a percentage of its average girdle diameter.
a percentage of its average girdle diameter.
275
```
Which of the following typically has a waxy to granular girdle surface?
A. CZ
B. GGG
C. Diamond
D. Synthetic rutile
```
Diamond
276
```
The combined effect of all the diamond’s surface and internal white light reflections is its
A. brightness.
B. reflectivity.
C. scintillation.
D. transmission.
```
brightness.
277
```
When boron is present in a diamond’s crystal structure, it colors the diamond
A. red.
B. pink.
C. blue.
D. green.
```
blue.
278
The setting that makes it most difficult to estimate a stone’s weight is a
A. bezel setting with an open back.
B. bezel setting with a closed back.
C. six-prong setting with a closed back.
D. four-prong setting with an open back.
bezel setting with a closed back.
279
```
Squares or rectangles, trigons, and parallel grooves are types of
A. macles.
B. graining.
C. twin crystals.
D. growth marks.
```
growth marks.
280
```
Substantial price discounts are available to retailers and jewelry manufacturers who
A. travel to diamond mines.
B. can buy in large quantities.
C. buy small quantities every month.
D. always buy from the same supplier.
```
can buy in large quantities.
281
```
Which of the following properties is higher in GGG than in diamond?
A. Doubling
B. Dispersion
C. Specific gravity
D. Thermal conductivity
```
Specific gravity
282
A diamond grading system provides
A. exact diamond market value to a buyer.
B. a consistent way to communicate diamond quality.
C. assurance to customers that they’re getting the best prices.
D. diamond descriptions that can change from country to country.
a consistent way to communicate diamond quality.
283
When you judge a diamond’s shape appeal, you consider
A. its bulge factor.
B. its total depth percentage.
C. the symmetry of its corresponding parts.
D. whether or not its shape is graceful and pleasing.
whether or not its shape is graceful and pleasing.
284
```
An estimation of the value of an article is a(n)
A. grade.
B. appraisal.
C. price guide.
D. insurance policy.
```
appraisal.
285
```
The flash effect proves that a diamond
A. is coated.
B. is irradiated.
C. is fracture-filled.
D. has undergone HPHT treatment.
```
is fracture-filled.
286
Most of the world’s kimberlite pipes
A. are located close to large cities.
B. are being mined for diamonds at the present.
C. do not contain diamonds in profitable quantities.
D. are believed to contain great quantities of diamonds.
do not contain diamonds in profitable quantities.
287
```
The deep vertical formations through which diamonds traveled to the surface are called
A. drifts.
B. pipes.
C. cratons.
D. alluvials.
```
pipes.
288
GIA Laboratory and other gemological laboratories
A. don’t grade fracture-filled diamonds.
B. grade diamonds before they fracture fill them.
C. only treat diamonds with eye-visible feathers.
D. give fracture-filled diamonds grades that are one grade lower than they appear to be.
don’t grade fracture-filled diamonds.
289
```
White light is actually
A. shortwave radiation.
B. the result of dispersion.
C. the result of transmission.
D. a combination of all the spectral colors.
```
a combination of all the spectral colors.
290
```
Which of the following GIA color grades indicates the greatest amount of yellow?
A. D
B. F
C. G
D. H
```
H
291
```
When a gem absorbs some wavelengths of light and transmits others, the process is called
A. color selection.
B. spectral absorption.
C. selective absorption.
D. selective transmission.
```
selective absorption.
292
```
Diamond imitations called “paste” are actually
A. glass.
B. zircon.
C. synthetic spinel.
D. rock crystal quartz.
```
glass.
293
```
Indicator minerals in kimberlite and lamproite might include tiny
A. emeralds.
B. sapphires.
C. amethysts.
D. diamonds.
```
diamonds.
294
```
Diamonds that are colorless to light yellow and light brown fall into the
A. bodycolor range.
B. basic color range.
C. normal color range.
D. tone and saturation range.
```
normal color range.
295
```
A weight-retention method that adjusts the angles of some facets to allow portions of a diamond’s girdle to be thicker is called
A. painting.
B. digging out.
C. brillianteering.
D. final polishing.
```
painting.
296
```
Inclusions are easier to see using
A. ultraviolet light.
B. darkfield illumination.
C. overhead spot lighting.
D. overhead fluorescent lighting.
```
darkfield illumination.
297
```
The flashes of light and the contrasting dark areas you see when the diamond, the light, or the observer moves are called
A. extinction.
B. dispersion.
C. scintillation.
D. transmission.
```
scintillation.
298
Diamond’s attraction to grease is used in
A. separating diamond from ore gravels.
B. fashioning diamond into fancy shapes.
C. separating gem-quality from industrial diamonds.
D. sorting and grading operations at the Diamond Trading Company.
separating diamond from ore gravels.
299
```
How far beneath the earth’s surface do diamonds form?
A. 15 to 30 miles (25 to 50 km)
B. 30to50miles(50to75km)
C. 50 to 90 miles (75 to 140 km)
D. 90 to 140 miles (140 to 220 km)
```
90 to 140 miles (140 to 220 km)
300
```
Trigons are
A. drag lines.
B. color centers.
C. growth marks.
D. twinning planes.
```
growth marks.
301
```
Russia’s diamond sources are almost all
A. alluvial.
B. primary.
C. depleted.
D. secondary.
```
primary.
