LATEST GIA COLORED STONE FINAL EXAM ACTUAL
QUESTIONS AND CORRECT DETAILED ANSWERS (100%
CORRECT VERIFIED ANSWERS) A NEW UPDATED
VERSION | GUARANTEED PASS. (FULL REVISED EXAM)
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.
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.
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.
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.
, Color zoning - ANSWER: Areas of different color in a gem, caused by variations in
growth conditions.
Colorless impregnation - ANSWER: Filling of pores or other openings with melted
wax, resin, polymer, or plastic to improve appearance and stability.
Commercial market - ANSWER: Market sector where average-quality gemstones are
used in mass-market jewelry.
Conchiolin - ANSWER: The organic "glue" in nacre that holds aragonite platelets
together.
Conchoidal fracture - ANSWER: A curved and ridged fracture in a gemstone,
extending from the surface inward.
Consignment - ANSWER: A selection of goods loaned to a dealer by another
wholesaler or gem cutter.
Contact metamorphism - ANSWER: Localized changes caused by an igneous intrusion
that takes place where the magma meets the surrounding rock. New minerals may
form due to temperature changes or introduction of fluids from the magma.
Core - ANSWER: The earth's innermost layer.
Crazing - ANSWER: The network of tiny fractures that develop when opal loses
moisture.
Crown - ANSWER: Top part of the gem above the girdle.
Crown-height to pavilion-depth ratio - ANSWER: The relationship of the height of a
gem's crown to the depth of its pavilion, judged by viewing its profile,
Crust - ANSWER: The surface and outermost later of the earth.
Cryptocystalline - ANSWER: An aggregate made up of individual crystals detectable
only under very high magnification.
Crystal structure - ANSWER: Regular, repeating internal arrangement of atoms in a
material.
Cultured blister pearl - ANSWER: A cultured pearl grown around a nucleus glued
under the mantle tissue inside a mollusk's shell.
Cultured pearl - ANSWER: A pearl formed as the result of human intervention in the
formation process.
QUESTIONS AND CORRECT DETAILED ANSWERS (100%
CORRECT VERIFIED ANSWERS) A NEW UPDATED
VERSION | GUARANTEED PASS. (FULL REVISED EXAM)
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.
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.
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.
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.
, Color zoning - ANSWER: Areas of different color in a gem, caused by variations in
growth conditions.
Colorless impregnation - ANSWER: Filling of pores or other openings with melted
wax, resin, polymer, or plastic to improve appearance and stability.
Commercial market - ANSWER: Market sector where average-quality gemstones are
used in mass-market jewelry.
Conchiolin - ANSWER: The organic "glue" in nacre that holds aragonite platelets
together.
Conchoidal fracture - ANSWER: A curved and ridged fracture in a gemstone,
extending from the surface inward.
Consignment - ANSWER: A selection of goods loaned to a dealer by another
wholesaler or gem cutter.
Contact metamorphism - ANSWER: Localized changes caused by an igneous intrusion
that takes place where the magma meets the surrounding rock. New minerals may
form due to temperature changes or introduction of fluids from the magma.
Core - ANSWER: The earth's innermost layer.
Crazing - ANSWER: The network of tiny fractures that develop when opal loses
moisture.
Crown - ANSWER: Top part of the gem above the girdle.
Crown-height to pavilion-depth ratio - ANSWER: The relationship of the height of a
gem's crown to the depth of its pavilion, judged by viewing its profile,
Crust - ANSWER: The surface and outermost later of the earth.
Cryptocystalline - ANSWER: An aggregate made up of individual crystals detectable
only under very high magnification.
Crystal structure - ANSWER: Regular, repeating internal arrangement of atoms in a
material.
Cultured blister pearl - ANSWER: A cultured pearl grown around a nucleus glued
under the mantle tissue inside a mollusk's shell.
Cultured pearl - ANSWER: A pearl formed as the result of human intervention in the
formation process.
