GIA Diamonds and Diamond Grading
Final Exam 2
$20,000 - ANS - What is the per-carat price of a 2ct diamond selling for $40,000?
\2:1 - ANS - What is the length-to-width ratio for a fancy cut 4.00mm long and 2.00mm wide?
\3.52 - ANS - What is the specific gravity of a gem-quality diamond?
\37% - ANS - What pavilion depth percentage might reflect the girdle face-up through the table?
\8 - ANS - How many star facet lengths on a round brilliant diamond are estimated before
averaging?
\90-140 miles (140-220 km) - ANS - How far beneath the earth do diamonds form?
\A diamond's absorption of visible light, portions or UV light and infrared regions close to the
visible range - ANS - What can UV-Vis-NIR spectroscopy help identify?
\A good sign that a pipe is nearby - ANS - What might black spinel in a mineral sample indicate?
\Allowing for greater weight retention from rough - ANS - The rotary saw contributed to the
diamond cutting industry by
\Annealing - ANS - Using heat to stabilize irradiated color in gemstones
- when used following irradiation (2-step process) it produces brown, orange, or yellow and can
rarely produce pink, red, or purple
\Annealing - ANS - What diamond color treatment further modifies color by allowing vacancies
and trace elements to diffuse post-irradiation?
\As a diamond's pavilion gets deeper, its table reflection becomes... - ANS - Larger
\At every step - ANS - When should the origin of a lab-grown diamond be disclosed?
\Baby Boomers - ANS - What generation was first to connect with diamonds as a representation
of lifetime commitment?
\Blemishes - ANS - What clarity characteristic is found only on the surface of a gemstone?
\Blocker - ANS - Polishes the crown and pavilion mains
\Bourse - ANS - A diamond buying and selling club (they have them in trading centers)
\Brazil - ANS - Where are rocks and geological structures similar to Africa found due to ancient
connections?
\Brillianteering - ANS - Polishing of the star and upper and lower half facets
\Bruise - ANS - A surface indentation with tiny, root-like feathers penetrating the stone is called a
_____
\Bruting - ANS - What made true round-shaped diamonds possible?
\Calibration - ANS - What does an electronic scale require immediately after is it leveled for
accurate measurement?
\Cavity - ANS - What clarity characteristic results when a crystal is expelled?
\Chambering - ANS - An older underground mining technique
- expensive and dangerous (no longer used)
- block caving is the alternative to this
\Character sampling - ANS - What type of sampling gives an initial idea of diamond quality for a
deposit?
, \Cleavage - ANS - What is a smooth, flat break in a crystal parallel to a cleavage plane?
\Cleaving - ANS - What process splits diamond rough along its cleavage plane?
\CLIPPIR diamonds, blue diamonds, Brazil's Junia diamond - ANS - What is an example of a
superdeep diamond?
\Cloud - ANS - Many tightly grouped pinpoints
\Cloud or pinpoint - ANS - What kind of clarity characteristic is not seen at 10x mag.?
\Color - ANS - How are gem-quality rough diamonds sorted?
\Color center - ANS - What influences light absorption, resulting in bodycolor?
\Craftsmanship - ANS - The care that goes into the fashioning of a polished diamond, as
confirmed by its finish
\Crystal structure - ANS - What is another term for crystal lattice?
\Cubic (runs horizontal), octahedral (on face), dodecahedral (runs vertical) - ANS - What are
diamond's 3 internal crystal planes?
\Cuboctahedrons - ANS - What rough form does NOT appear in natural diamonds
\Culet size should be considered when determining... - ANS - Pavilion depth percentage
\Cutting - ANS - What controls light path length within a diamond?
\CVD lab-grown diamonds - ANS - What diamonds have strain pattern and intensity similar to
natural diamonds?
\De Beers Consolidated Mines Ltd. - ANS - Was named after the owners of a farm where one of
the first diamond rushes took place
\Degree of darkness or lightness - ANS - What is a term that describes tone?
\Design - ANS - A diamond's physical shape, including its proportions and durability, determined
by decisions made during the fashioning process
\Determine which proportion combinations create the most attractive light performance - ANS -
What was the main goal of research in developing the GIA Cut Grading System?
\Diamantaire - ANS - What term describes an expert diamond dealer or manufacturer?
\Diamond simulants called "paste" are... - ANS - Glass
\Diamond types - ANS - Ia: abundant, plentiful nitrogen; near-colorless to yellow
Ib: rare, less nitrogen than Ia; more yellow than Ia
IIa: very rare, little to no nitrogen; colorless, brown, or gray
IIb: very rare, contains boron, little to no nitrogen; blue
\Diamond's girdle surface is usually a... - ANS - Waxy to granular surface
\Diamonds - ANS - What material are masterstones?
\Directly under the table - ANS - Where are inclusions most visible?
\Dodecahedral - ANS - What is the softest crystal direction in diamond?
\Drift - ANS - A horizontal tunnel drilled through a diamond pipe
\Eglogite - ANS - A type of rock that diamonds for in
- metamorphic rock (rocks that have been altered by heat and pressure)
- does not have a consistent release of carbon
\Excellent cut grades corresponding total depth % is... - ANS - 57.5-63%
\Face-up - ANS - What position are colored diamonds color graded in?
\Fair cut grades corresponding total depth % is... - ANS - 51-70.9%
\Finish - ANS - The quality of the polish and precision of the cut of a fashioned gemstone
\Fire - ANS - What can help rapidly identify a strontium titanate doublet?
Final Exam 2
$20,000 - ANS - What is the per-carat price of a 2ct diamond selling for $40,000?
\2:1 - ANS - What is the length-to-width ratio for a fancy cut 4.00mm long and 2.00mm wide?
\3.52 - ANS - What is the specific gravity of a gem-quality diamond?
\37% - ANS - What pavilion depth percentage might reflect the girdle face-up through the table?
\8 - ANS - How many star facet lengths on a round brilliant diamond are estimated before
averaging?
\90-140 miles (140-220 km) - ANS - How far beneath the earth do diamonds form?
\A diamond's absorption of visible light, portions or UV light and infrared regions close to the
visible range - ANS - What can UV-Vis-NIR spectroscopy help identify?
\A good sign that a pipe is nearby - ANS - What might black spinel in a mineral sample indicate?
\Allowing for greater weight retention from rough - ANS - The rotary saw contributed to the
diamond cutting industry by
\Annealing - ANS - Using heat to stabilize irradiated color in gemstones
- when used following irradiation (2-step process) it produces brown, orange, or yellow and can
rarely produce pink, red, or purple
\Annealing - ANS - What diamond color treatment further modifies color by allowing vacancies
and trace elements to diffuse post-irradiation?
\As a diamond's pavilion gets deeper, its table reflection becomes... - ANS - Larger
\At every step - ANS - When should the origin of a lab-grown diamond be disclosed?
\Baby Boomers - ANS - What generation was first to connect with diamonds as a representation
of lifetime commitment?
\Blemishes - ANS - What clarity characteristic is found only on the surface of a gemstone?
\Blocker - ANS - Polishes the crown and pavilion mains
\Bourse - ANS - A diamond buying and selling club (they have them in trading centers)
\Brazil - ANS - Where are rocks and geological structures similar to Africa found due to ancient
connections?
\Brillianteering - ANS - Polishing of the star and upper and lower half facets
\Bruise - ANS - A surface indentation with tiny, root-like feathers penetrating the stone is called a
_____
\Bruting - ANS - What made true round-shaped diamonds possible?
\Calibration - ANS - What does an electronic scale require immediately after is it leveled for
accurate measurement?
\Cavity - ANS - What clarity characteristic results when a crystal is expelled?
\Chambering - ANS - An older underground mining technique
- expensive and dangerous (no longer used)
- block caving is the alternative to this
\Character sampling - ANS - What type of sampling gives an initial idea of diamond quality for a
deposit?
, \Cleavage - ANS - What is a smooth, flat break in a crystal parallel to a cleavage plane?
\Cleaving - ANS - What process splits diamond rough along its cleavage plane?
\CLIPPIR diamonds, blue diamonds, Brazil's Junia diamond - ANS - What is an example of a
superdeep diamond?
\Cloud - ANS - Many tightly grouped pinpoints
\Cloud or pinpoint - ANS - What kind of clarity characteristic is not seen at 10x mag.?
\Color - ANS - How are gem-quality rough diamonds sorted?
\Color center - ANS - What influences light absorption, resulting in bodycolor?
\Craftsmanship - ANS - The care that goes into the fashioning of a polished diamond, as
confirmed by its finish
\Crystal structure - ANS - What is another term for crystal lattice?
\Cubic (runs horizontal), octahedral (on face), dodecahedral (runs vertical) - ANS - What are
diamond's 3 internal crystal planes?
\Cuboctahedrons - ANS - What rough form does NOT appear in natural diamonds
\Culet size should be considered when determining... - ANS - Pavilion depth percentage
\Cutting - ANS - What controls light path length within a diamond?
\CVD lab-grown diamonds - ANS - What diamonds have strain pattern and intensity similar to
natural diamonds?
\De Beers Consolidated Mines Ltd. - ANS - Was named after the owners of a farm where one of
the first diamond rushes took place
\Degree of darkness or lightness - ANS - What is a term that describes tone?
\Design - ANS - A diamond's physical shape, including its proportions and durability, determined
by decisions made during the fashioning process
\Determine which proportion combinations create the most attractive light performance - ANS -
What was the main goal of research in developing the GIA Cut Grading System?
\Diamantaire - ANS - What term describes an expert diamond dealer or manufacturer?
\Diamond simulants called "paste" are... - ANS - Glass
\Diamond types - ANS - Ia: abundant, plentiful nitrogen; near-colorless to yellow
Ib: rare, less nitrogen than Ia; more yellow than Ia
IIa: very rare, little to no nitrogen; colorless, brown, or gray
IIb: very rare, contains boron, little to no nitrogen; blue
\Diamond's girdle surface is usually a... - ANS - Waxy to granular surface
\Diamonds - ANS - What material are masterstones?
\Directly under the table - ANS - Where are inclusions most visible?
\Dodecahedral - ANS - What is the softest crystal direction in diamond?
\Drift - ANS - A horizontal tunnel drilled through a diamond pipe
\Eglogite - ANS - A type of rock that diamonds for in
- metamorphic rock (rocks that have been altered by heat and pressure)
- does not have a consistent release of carbon
\Excellent cut grades corresponding total depth % is... - ANS - 57.5-63%
\Face-up - ANS - What position are colored diamonds color graded in?
\Fair cut grades corresponding total depth % is... - ANS - 51-70.9%
\Finish - ANS - The quality of the polish and precision of the cut of a fashioned gemstone
\Fire - ANS - What can help rapidly identify a strontium titanate doublet?
