Study Questions for Sections 10 & 11
Section 10
10.02
#1 In buying a mounted diamond the risk of inaccurate
grading is greater than it would be for a loose diamond.
A. True
B. False
10.03
#1 A 6.7 mm round brilliant cut diamond will always weigh
more than 1.00 carat.
A. True
B. False
10.04
#1 Always assume a private party seller has intentionally
deceived you when a mounted diamond has a chip that
was hidden under a prong.
A. Yes
B. No
10.05
#1 Which of the following scenarios could most likely allow
a 6.7 mm diameter round brilliant cut diamond to weigh less
than 0.90 carat?
A. A 64% table with a 60.2% depth.
B. A 64% table with 39.5 degree pavilion angles and a
59.5% depth.
C. A 64% table with 32.5 degree pavilion angles and a
10% crown.
#2 Which of the following characteristics would be the
most obvious in identifying a very fl at pavilion?
A. The “Table Reflection Method” displaying a
reflection 1/3 of the way to the table edge.
B. A girdle reflection inside the table.
C. A darkness in the center of the diamond.
10.06
#1 A diamond mounted in yellow gold could make a “K”
color more difficult to grade.
A. True
B. False
10.07
#1 Which of the following set of characteristics would most
likely give the illusion of a “K” color having the appearance
of an “H” color?
A. Faint blue fluorescence mounted in platinum.
B. Strong blue fluorescence loose on a grading tray.
C. Strong blue fluorescence mounted in yellow gold
prongs.
10.08
#1 Which method would be the most decisive in detecting
blue fluorescence?
A. Exposing it to long wave ultraviolet light.
B. Exposing it to short wave ultraviolet light.
C. Exposing it to indirect sunlight.
#2 Strong blue fluorescence could potentially raise the
value of a diamond in lower colors.
A. True
B. False
# 3 The safest approach in making an offer on a diamond
is to…
A. make it very low.
B. do it contingent upon the presumed grade until it
has been removed from the mounting.
C. demand your money back if you are disappointed
in the grade and weight.
Section 11
11.01
#1 It is never possible to get a close weight estimation in a
mounted diamond.
A. True
B. False
11.02
#1 What is the increment and system of measurement
used in the diamond trade?
A. Fractions of an inch.
B. Millimeters in the metric system.
C. Centimeters in the metric system.
11.03
#1 A diamond that has a diameter of 7.23 means…
A. 23/100ths of a centimeter over 7 centimeters.
B. 23/100ths of a millimeter over 7 millimeters.
C. 23/10ths of a millimeter over 7 millimeters.
#2 Which of the following descriptions is the closest to six
and a half millimeters?
A. 6.21
B. 6.05
C. 6.005
11.04
#1 A hole gauge is the most accurate method of estimating
diamond weight.
A. True
B. False
#2 Diamond sieves are used to…
A. estimate melee weight.
B. sort melee into size categories.
C. estimate any size diamond.
11.05
#1 A 0.46 ct. diamond could commonly be expressed
as…
A. a light half.
B. a half.
C. three-eighths.
D. none of the above.
#2 A 0.85 ct. diamond would most commonly be expressed
as…
A. an eighty-five carater.
B. an eighty-five pointer.
C. a light carat.
#3 The least common expression of a 1.65 ct. diamond
is…
A. a carat sixty-five.
B. one-point-six-five carats.
C. a hundred and sixty-five points.
#4 A 0.75 ct. diamond could also be referred to as a three-
grainer.
A. True
B. False
11.06
#1 A major reason for the necessity of weight estimation
formulas is the fact that diamonds are…
A. inconsistent in proportions.
B. inconsistent in specific gravity.
C. consistent in angles.
11.07
#1 In adjusting a formula for girdle thickness which of the
following would not apply?
A. Thin Girdle
B. Medium Girdle
C. Thick Girdle
#2 Generally the thicker the girdle the more the diamond
will weigh, given the same diameter.
A. True
B. False
#3 A girdle that is “Thin to Slightly Thick” could potentially
be an average of…
A. medium.
B. thick.
C. very thick.
#4 It is unusual to find thick girdles on fancy shapes.
A. True
B. False
#5 If a 0.20 ct. diamond and a 1.20 ct. diamond were both
described as having an average girdle of “thick” the “Girdle
Thickness Adjustment” operator would be the same.
A. True
B. False
11.08
#1 Averaging a girdle thickness for the purposes of the
“Girdle Thickness Adjustment” the operator is somewhat of a
judgment call.
A. True
B. False
#2 Which of the following “Medium to Thick” diamond
girdles would need the largest adjustment in the GTA
operator?
A. 50% medium, 50% thick
B. 25% medium, 75% thick
C. 10% medium, 90% thick
11.09
#1 Dealers who are too conservative in their weight
estimates may at times look…
A. like smart businessmen.
B. dishonest.
C. unprofessional.
D. B & C.
E. all of the above.
11.10
#1 The oval weight estimation formula is as follows:
A. Average diameter x average diameter x depth x
.0062
B. Average diameter x average diameter x depth x
.0061
C. Length x width x depth x
.0062
#2 With your calculator formulate the weight for the
following described round brilliant cut diamond:
Narrowest diameter: 6.04 mm
Widest diameter: 6.17 mm
Depth: 4.01 mm
Medium Girdle
A. 0.85 ct.
B. 0.91 ct.
C. 0.99 ct.
#3 With your calculator formulate the weight for the
following described round brilliant cut diamond:
Narrowest diameter: 5.32
Widest diameter: 5.41
Depth: 2.87
Thick Girdle GTA: 1.03
A. 0.45 ct.
B. 0.48 ct.
C. 0.52 ct.
1.03
#4 With your calculator formulate the weight for the
following described round brilliant diamond:
Narrowest diameter: 8.31 mm
Widest diameter: 8.49 mm
Depth: 5.76 mm
Thin to Extremely Thin Girdle GTA: 0.95
A. 2.35 ct.
B. 2.44 ct.
C. 2.56 ct.
#4 If a diamond weighs 0.568 ct. it would be expressed as:
A. 0.56 ct.
B. 0.57 ct.
C. 0.58 ct.
#6 If the results of a weight estimation formula was 0.999 it
would be expressed as…
A. 0.99 ct.
B. 0.999 ct.
C. 1.00 ct.
#7 If the results of a weight estimation formula was 1.235 it
would be expressed as…
A. 1.23 ct.
B. 1.24 ct.
C. 1.25 ct.
11.11
#1 One difficulty of measuring a marquise or pear shape
for weight estimation in a mounting is compensating for
pronged end(s).
A. True
B. False
11.12
#1 In addition to the GTA (Girdle Thickness Adjustment)
which of the following characteristics in a pear shape
diamond weight estimate formula would need to be considered?
A. Flat pavilion angles.
B. High shoulders.
C. A small table.
#2 In addition to the GTA (Girdle Thickness Adjustment)
which of the following characteristics in an emerald cut
diamond weight estimate formula would need to be considered?
A. Pavilion angles below 42 degrees.
B. Crown angles over 35 degrees.
C. A pronounced pavilion bulge.
11.13
#1 The width is not always expressed as “1” in a Length to
Width Ratio.
A. True
B. False
#2 Given the following measurements of an emerald cut
diamond what would the correct Length to Width Ratio be?
Length: 8.23 mm
Width: 6.78 mm
Depth: 4.85 mm
A. 1.25 to 1 L/W
B. 1.21 to 1 L/W
C. 1.18 to 1 L/W
#3 Given the following measurements of a marquise cut
diamond what would the correct Length to Width Ratio be?
Length: 11.36mm
Width: 5.76 mm
Depth: 3.25 mm
A. 2.11 to 1 L/W
B. 2.00 to 1 L/W
C. 1.97 to 1 L/W
11.14
#1 Given the following measurements of a marquise cut
diamond what is the correct weight estimation?
Length: 9.03 mm
Width: 5.21 mm
Depth: 3.87 mm
Girdle Very Thick
L/W ratio LWA
1.50/1.00 .00565
1.75/1.00 .00570
2.00/1.00 .00580
2.25/1.00 .00583
2.50/1.00 .00585
2.75/1.00 .00590
3.00/1.00 .00595
A. 1.09 ct.
B. 1.12 ct.
C. 1.15 ct.
11.15
#1 Given the following measurements of an emerald cut
diamond what is the correct weight estimation?
Length: 7.52 mm
Width: 5.05 mm
Depth: 3.81 mm
Girdle Very Thick-: GTA 1.05
Please refer to the following table:
L/W ratio LWA
1.00/1.00 .0080
1.50/1.00 .0092
1.75/1.00 .0097
2.00/1.00 .0100
2.25/1.00 .0104
2.50/1.00 .0106
A. 1.25 ct.
B. 1.35 ct.
C. 1.39 ct.
11.16
#1 Given the following measurements for a tapered baguette what is the correct weight estimation?
Length: 4.72 mm
Wider End Width: 2.15 mm
Narrower End Width: 1.63 mm
Depth: 1.51 mm
A. 0.14 ct.
B. 0.13 ct.
C. 0.12 ct.
#2 A straight baguette weight estimate formula most closely resembles the...
A. marquise weight estimate formula.
B. emerald cut weight estimate formula.
C. oval weight estimate formula.
11.17
#1 Given the following measurements of a pear shape
diamond what is the correct weight estimation?
Length: 5.45 mm
Width: 4.34 mm
Depth: 3.06 mm
Girdle Very Thick-: GTA 1.05
Please refer to the following table:
L/W Ratio
1.25/1.00
1.50/1.00
1.66/1.00
2.00/1.00
A. 0.40 ct.
B. 0.46 ct.
C. 0.51 ct.
LWA
.00615
.00600
.00590
.00575
11.18
#1 Given the following measurements of an oval shape
diamond what is the correct weight estimation?
Length:11.05 mm
Width: 8.76mm
Depth: 5.85 mm
Girdle Very Thick-: GTA 1.035
Additional Adjustment for Cushion Shape: 1.03
A. 2.48 ct.
B. 3.03 ct.
C. 3.79 ct.
11.19
#1 Given the following measurements of a heart shape
diamond what is the correct weight estimation?
Length: 10.55 mm
Width: 9.98 mm
Depth: 4.85 mm- 142
Girdle Very Thick-: GTA 1.035
A. 3.11 ct.
B. 3.21 ct.
C. 3.31 ct.
11.20
#1 Given the following measurements of a triangular
brilliant diamond what is the correct weight estimation?
Length: 4.21mm
Width: 4.05 mm
Depth: 2.87 mm
Girdle Thick: GTA 1.04
A. 0.25 ct.
B. 0.29 ct.
C. 0.33 ct.