GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Mineral - (ANSWER)A natural, inorganic substance with a characteristic chemical composition and
usually characteristic structure.
Mixed cut - (ANSWER)A cutting style that combines brilliant-cut and step cut facets.
Abrasions - (ANSWER)Tiny nicks and pits caused by wear and damage to a gem's facet edges or culet.
Absorption spectrum - (ANSWER)A pattern of dark vertical lines or bands shown by certain gems when
viewed through a spectroscope.
Adularescence - (ANSWER)The cloudy bluish white light in a moonstone, caused by scattering of light.
Agate - (ANSWER)Chalcedony with a curved or angular bands or layers that differ in color and
transparency .
Aggregate - (ANSWER)A mass of tiny, randomly oriented crystals.
Akoya - (ANSWER)Common name for the Pinctada fucata oyster and the natural or cultured pearls it
produces.
Allochromatic - (ANSWER)A gem colored by trace elements in its crystal structure.
Alluvial deposit - (ANSWER)A deposit where gems are eroded from their source rock, then transported
away from their source and further concentrated.
Amorphous - (ANSWER)Lacking a regular crystal structure.
Aragonite - (ANSWER)A crystalized form of calcium carbonate found in nacre.
,GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Assembled stone - (ANSWER)Two or more separate pieces of material joined to form a unit.
Asterism - (ANSWER)Crossing of chatoyant bands, creating a star in the dome of cabochon.
Atom - (ANSWER)The basic structural unit of all matter.
Aventurescence - (ANSWER)A glittery effect caused by light reflecting from small, flat inclusions within a
gemstone.
Background color - (ANSWER)An opal's bodycolor, independent of its play-of-color.
Bead nucleus - (ANSWER)A bead used as the core of a cultured pearl, usually made from a freshwater
mussel shell.
Bleaching - (ANSWER)A treatment that uses chemicals to lighten or remove color.
Blemish - (ANSWER)Characteristic or irregularity confined to the surface of a polished gemstone.
Blue Sheen - (ANSWER)Trade term for a highly prized, vivid blue adularescence displayed by the finest
moonstone.
Bodycolor - (ANSWER)A gemstone's basic color, determined by its selective absorption of light.
Botryoidal - (ANSWER)A crystal growth habit with a bumpy appearance similar to a bunch of grapes.
Boulder opal - (ANSWER)Thin layers of precious opal, cut to include matrix.
Boule - (ANSWER)A cylindrical synthetic crystal produced by the flame-fusion process.
,GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Brilliance - (ANSWER)Light that eventually returns to the eye after entering a gem through the crown,
reflecting off its pavilion facets, and exiting back through the crown.
Brilliant cut - (ANSWER)Cutting style with triangular or kite-shaped facets that radiate from the center
toward girdle.
Cabochon - (ANSWER)A smoothly rounded polished gem with a domed top and a flat or curved base.
Calcareous concretion - (ANSWER)A non-nacreous natural "pearl".
Calibrated sizes - (ANSWER)Gemstone sizes cut to fit standard mountings.
Cameo - (ANSWER)A gem carving style in which the design often a women's profile, projects slightly
from a flat or curved surface.
Cavity - (ANSWER)An opening that extends into a gem from the surface.
Centipedes - (ANSWER)Tiny tension cracks in a moonstone that interfere with adularescence and reduce
value.
Ceramic process - (ANSWER)A process in which ground powder is heated, sometimes under pressure, to
produce a fine-grained solid material.
Certificate of origin - (ANSWER)A document that indicates a stone's geographic origin, based on its
inclusions and trace element chemistry.
Chalcedony - (ANSWER)A cryptocrystalline quartz aggregate.
Charge transfer - (ANSWER)A process where the electrons that selectively absorb light are passed back
and forth between neighboring impurity ions.
, GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Chatoyancy - (ANSWER)Bands of light in certain gems, caused by reflection of light from many parallel,
needle-like inclusions or hollow tubes.
Chemical composition - (ANSWER)Kinds and relative quantities of atoms that make up a material.
Chemical element - (ANSWER)A substance that consists of atoms of only one kind.
Chip - (ANSWER)A damaged area on a gem, usually near the girdle.
Chrome tourmaline - (ANSWER)Trade term for a vibrant green tourmaline that's colored by traces of
vanadium, chromium, or both.
Circled pearl - (ANSWER)A pearl with one or more grooved or ridged rings all the way around it.
Cleavage - (ANSWER)A smooth, flat break in a gemstone parallel to planes of atomic weakness, caused
by weak or fewer bonds between atoms or both.
Cloud - (ANSWER)Any hazy or milky area that cannot be described as a feather, fingerprint, or group of
included crystals or needles.
Cobbing - (ANSWER)Removing heavily included sections from a gemstone rough by carefully tapping it
with a small hammer.
Color center - (ANSWER)A small defect in the atomic structure of a material that absorb light and give
rise to a color.
Color Change - (ANSWER)A distinct change in gem color under different types of lighting.
Color range - (ANSWER)The selection of colors in which a gemstone occurs.
UPDATE | ALREADY PASSED!!
Mineral - (ANSWER)A natural, inorganic substance with a characteristic chemical composition and
usually characteristic structure.
Mixed cut - (ANSWER)A cutting style that combines brilliant-cut and step cut facets.
Abrasions - (ANSWER)Tiny nicks and pits caused by wear and damage to a gem's facet edges or culet.
Absorption spectrum - (ANSWER)A pattern of dark vertical lines or bands shown by certain gems when
viewed through a spectroscope.
Adularescence - (ANSWER)The cloudy bluish white light in a moonstone, caused by scattering of light.
Agate - (ANSWER)Chalcedony with a curved or angular bands or layers that differ in color and
transparency .
Aggregate - (ANSWER)A mass of tiny, randomly oriented crystals.
Akoya - (ANSWER)Common name for the Pinctada fucata oyster and the natural or cultured pearls it
produces.
Allochromatic - (ANSWER)A gem colored by trace elements in its crystal structure.
Alluvial deposit - (ANSWER)A deposit where gems are eroded from their source rock, then transported
away from their source and further concentrated.
Amorphous - (ANSWER)Lacking a regular crystal structure.
Aragonite - (ANSWER)A crystalized form of calcium carbonate found in nacre.
,GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Assembled stone - (ANSWER)Two or more separate pieces of material joined to form a unit.
Asterism - (ANSWER)Crossing of chatoyant bands, creating a star in the dome of cabochon.
Atom - (ANSWER)The basic structural unit of all matter.
Aventurescence - (ANSWER)A glittery effect caused by light reflecting from small, flat inclusions within a
gemstone.
Background color - (ANSWER)An opal's bodycolor, independent of its play-of-color.
Bead nucleus - (ANSWER)A bead used as the core of a cultured pearl, usually made from a freshwater
mussel shell.
Bleaching - (ANSWER)A treatment that uses chemicals to lighten or remove color.
Blemish - (ANSWER)Characteristic or irregularity confined to the surface of a polished gemstone.
Blue Sheen - (ANSWER)Trade term for a highly prized, vivid blue adularescence displayed by the finest
moonstone.
Bodycolor - (ANSWER)A gemstone's basic color, determined by its selective absorption of light.
Botryoidal - (ANSWER)A crystal growth habit with a bumpy appearance similar to a bunch of grapes.
Boulder opal - (ANSWER)Thin layers of precious opal, cut to include matrix.
Boule - (ANSWER)A cylindrical synthetic crystal produced by the flame-fusion process.
,GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Brilliance - (ANSWER)Light that eventually returns to the eye after entering a gem through the crown,
reflecting off its pavilion facets, and exiting back through the crown.
Brilliant cut - (ANSWER)Cutting style with triangular or kite-shaped facets that radiate from the center
toward girdle.
Cabochon - (ANSWER)A smoothly rounded polished gem with a domed top and a flat or curved base.
Calcareous concretion - (ANSWER)A non-nacreous natural "pearl".
Calibrated sizes - (ANSWER)Gemstone sizes cut to fit standard mountings.
Cameo - (ANSWER)A gem carving style in which the design often a women's profile, projects slightly
from a flat or curved surface.
Cavity - (ANSWER)An opening that extends into a gem from the surface.
Centipedes - (ANSWER)Tiny tension cracks in a moonstone that interfere with adularescence and reduce
value.
Ceramic process - (ANSWER)A process in which ground powder is heated, sometimes under pressure, to
produce a fine-grained solid material.
Certificate of origin - (ANSWER)A document that indicates a stone's geographic origin, based on its
inclusions and trace element chemistry.
Chalcedony - (ANSWER)A cryptocrystalline quartz aggregate.
Charge transfer - (ANSWER)A process where the electrons that selectively absorb light are passed back
and forth between neighboring impurity ions.
, GIA COLORED STONES ASSIGNMENT 7 | QUESTIONS AND ANSWERS | 2025/2026
UPDATE | ALREADY PASSED!!
Chatoyancy - (ANSWER)Bands of light in certain gems, caused by reflection of light from many parallel,
needle-like inclusions or hollow tubes.
Chemical composition - (ANSWER)Kinds and relative quantities of atoms that make up a material.
Chemical element - (ANSWER)A substance that consists of atoms of only one kind.
Chip - (ANSWER)A damaged area on a gem, usually near the girdle.
Chrome tourmaline - (ANSWER)Trade term for a vibrant green tourmaline that's colored by traces of
vanadium, chromium, or both.
Circled pearl - (ANSWER)A pearl with one or more grooved or ridged rings all the way around it.
Cleavage - (ANSWER)A smooth, flat break in a gemstone parallel to planes of atomic weakness, caused
by weak or fewer bonds between atoms or both.
Cloud - (ANSWER)Any hazy or milky area that cannot be described as a feather, fingerprint, or group of
included crystals or needles.
Cobbing - (ANSWER)Removing heavily included sections from a gemstone rough by carefully tapping it
with a small hammer.
Color center - (ANSWER)A small defect in the atomic structure of a material that absorb light and give
rise to a color.
Color Change - (ANSWER)A distinct change in gem color under different types of lighting.
Color range - (ANSWER)The selection of colors in which a gemstone occurs.
