DIAMOND & DIAMOND GRADING EXAM QUESTIONS
WITH COMPLETE SOLUTIONS GUARANTEED PASS
2025/2026
Chemical vapor deposition (CVD) -ANSWER - >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)
Chip (Ch) -ANSWER - >A shallow opening caused by damage to the
stone's surface; typically occurs at a girdle edge, facet junction, or culet.
(Assignment 10)
Clarity characteristic -ANSWER - >Internal or external feature of a
gemstone that helps determine its quality and establish its identity.
(Assignment 10)
Cleavage (Cl) -ANSWER - >Large, severe, straight break along a plane of
atomic weakness; considered an inclusion. (Assignment 10)
Cleavage plane -ANSWER - >Plane parallel to a possible crystal face,
where a diamond can split cleanly when struck. (Assignment 7)
Cleaver -ANSWER - >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)
Cleaving -ANSWER - >Dividing a diamond into two or more pieces along
a cleavage plane. (Assignment 9)
,Cloud (Cld) -ANSWER - >Many tightly grouped pinpoints that might be
too small to distinguish individually at 10X but together have a hazy
appearance. (Assignment 10)
Color center -ANSWER - >Structural defect that influences an object's
absorption of light and can cause its color. (Assignment 12)
Conflict diamonds -ANSWER - >Diamonds used to finance violence and
terror. (Assignment 3)
Consignment -ANSWER - >A selection of goods loaned to a dealer by
another wholesaler or manufacturer.
(Assignment 20)
Core -ANSWER - >Earth's innermost layer. (Assignment 4)
Covalent bond -ANSWER - >A chemical bond formed by
two atoms sharing electrons. (Assignment 7)
Craftsmanship -ANSWER - >The care that goes into the fashioning of a
polished diamond, as confirmed by its finish. (Assignment 15)
Cratons -ANSWER - >Ancient, large, and stable parts of the earth's
continental crust. (Assignment 4)
Critical angle -ANSWER - >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)
,Cross worker -ANSWER - >A person who performs the cross-working
operations during diamond polishing; sometimes called a cross cutter.
(Assignment 9)
Cross working -ANSWER - >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)
Crown angle -ANSWER - >The angle formed by the bezel facets and the
girdle plane. (Assignment 14)
Crown height percentage -ANSWER - >The distance from the girdle
plane to the table, expressed as a percentage of average girdle
diameter. (Assignment 14)
Crust -ANSWER - >The surface and outermost layer of the earth.
(Assignment 4)
Crystal -ANSWER - >Solid matter with atoms arranged in a regular,
repeating pattern. (Assignment 7)
Crystal (Xtl) -ANSWER - >A mineral crystal contained in a
diamond. (Assignment 10)
Crystal planes -ANSWER - >Internal directions parallel to a mineral's
unit cell surfaces. (Assignment 7)
Crystal shape (form) -ANSWER - >Geometric shape of a well-formed
crystal. (Assignment 7)
Crystal structure (lattice) -ANSWER - >Regular, repeating arrangement
of atoms in a mineral. (Assignment 7)
, Crystal systems -ANSWER - >Categories of crystals based on their
symmetry and internal structure. (Assignment 7)
Crystalline -ANSWER - >Composed of crystals or related to crystals.
(Assignment 7)
Culet size -ANSWER - >The size of the facet at the bottom of the
diamond where the pavilion mains meet.
(Assignment 15)
Cuttable rough -ANSWER - >Diamond rough with good enough size,
shape, clarity, and color to produce a polished stone suitable for use in
jewelry. (Assignment 5)
Cutting center -ANSWER - >A city, region, or country with a large
number of gemstone manufacturers. (Assignment
3)
Cutting style -ANSWER - >The arrangement of a gem's facets.
(Assignment 16)
Darkfield illumination -ANSWER - >Lighting of a diamond from the side
against a black, non-reflective background.
(Assignment 10)
Dense media separation -ANSWER - >A recovery process that separates
diamonds from lighter material. Also called heavy media separation.
(Assignment 6)
WITH COMPLETE SOLUTIONS GUARANTEED PASS
2025/2026
Chemical vapor deposition (CVD) -ANSWER - >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)
Chip (Ch) -ANSWER - >A shallow opening caused by damage to the
stone's surface; typically occurs at a girdle edge, facet junction, or culet.
(Assignment 10)
Clarity characteristic -ANSWER - >Internal or external feature of a
gemstone that helps determine its quality and establish its identity.
(Assignment 10)
Cleavage (Cl) -ANSWER - >Large, severe, straight break along a plane of
atomic weakness; considered an inclusion. (Assignment 10)
Cleavage plane -ANSWER - >Plane parallel to a possible crystal face,
where a diamond can split cleanly when struck. (Assignment 7)
Cleaver -ANSWER - >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)
Cleaving -ANSWER - >Dividing a diamond into two or more pieces along
a cleavage plane. (Assignment 9)
,Cloud (Cld) -ANSWER - >Many tightly grouped pinpoints that might be
too small to distinguish individually at 10X but together have a hazy
appearance. (Assignment 10)
Color center -ANSWER - >Structural defect that influences an object's
absorption of light and can cause its color. (Assignment 12)
Conflict diamonds -ANSWER - >Diamonds used to finance violence and
terror. (Assignment 3)
Consignment -ANSWER - >A selection of goods loaned to a dealer by
another wholesaler or manufacturer.
(Assignment 20)
Core -ANSWER - >Earth's innermost layer. (Assignment 4)
Covalent bond -ANSWER - >A chemical bond formed by
two atoms sharing electrons. (Assignment 7)
Craftsmanship -ANSWER - >The care that goes into the fashioning of a
polished diamond, as confirmed by its finish. (Assignment 15)
Cratons -ANSWER - >Ancient, large, and stable parts of the earth's
continental crust. (Assignment 4)
Critical angle -ANSWER - >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)
,Cross worker -ANSWER - >A person who performs the cross-working
operations during diamond polishing; sometimes called a cross cutter.
(Assignment 9)
Cross working -ANSWER - >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)
Crown angle -ANSWER - >The angle formed by the bezel facets and the
girdle plane. (Assignment 14)
Crown height percentage -ANSWER - >The distance from the girdle
plane to the table, expressed as a percentage of average girdle
diameter. (Assignment 14)
Crust -ANSWER - >The surface and outermost layer of the earth.
(Assignment 4)
Crystal -ANSWER - >Solid matter with atoms arranged in a regular,
repeating pattern. (Assignment 7)
Crystal (Xtl) -ANSWER - >A mineral crystal contained in a
diamond. (Assignment 10)
Crystal planes -ANSWER - >Internal directions parallel to a mineral's
unit cell surfaces. (Assignment 7)
Crystal shape (form) -ANSWER - >Geometric shape of a well-formed
crystal. (Assignment 7)
Crystal structure (lattice) -ANSWER - >Regular, repeating arrangement
of atoms in a mineral. (Assignment 7)
, Crystal systems -ANSWER - >Categories of crystals based on their
symmetry and internal structure. (Assignment 7)
Crystalline -ANSWER - >Composed of crystals or related to crystals.
(Assignment 7)
Culet size -ANSWER - >The size of the facet at the bottom of the
diamond where the pavilion mains meet.
(Assignment 15)
Cuttable rough -ANSWER - >Diamond rough with good enough size,
shape, clarity, and color to produce a polished stone suitable for use in
jewelry. (Assignment 5)
Cutting center -ANSWER - >A city, region, or country with a large
number of gemstone manufacturers. (Assignment
3)
Cutting style -ANSWER - >The arrangement of a gem's facets.
(Assignment 16)
Darkfield illumination -ANSWER - >Lighting of a diamond from the side
against a black, non-reflective background.
(Assignment 10)
Dense media separation -ANSWER - >A recovery process that separates
diamonds from lighter material. Also called heavy media separation.
(Assignment 6)
