GIA COLORED STONE ESSENTIALS QUESTIONS AND CORRECT SOLUTIONS
COLORED STONE Any gem material other than diamond.
GEMOLOGY The study of gems.
ORGANIC Once living, or produced by a living organism (plant or animal).
MINERALS A natural, inorganic substance with a characteristic chemical composition and usually
characteristic structure.
INORGANIC Composed of, or arising from, non-living matter.
CHEMICAL COMPOSITIONS Kinds and relative quantities of atoms that make up a material.
DURABILITY A gemstone's ability to withstand wear, heat, and chemicals.
LUSTER The appearance of a material's surface in reflected light.
TRANSPARENCY Degree to which a material allows light to pass through it.
HARDNESS How well a gemstone resists scratches and abrasion.
TOUGHNESS How well a gemstone resists breaking, chipping, and cracking.
STABILITY How well a gemstone resists the effects of light, heat, and chemicals.
CRYSTAL STRUCTURE Regular, repeating internal arrangement of atoms in a material.
, GIA COLORED STONE ESSENTIALS QUESTIONS AND CORRECT SOLUTIONS
CHEMICAL FORMULA Written description of a material's chemical makeup.
TRACE ELEMENTS Atoms in a gem that aren't part of its essential chemical composition.
AMORPHOUS Lacking a regular crystal structure.
SPECIES A broad gem category based on chemical composition and crystal structure.
VARIETY A subcategory of species based on color, transparency, or phenomenon.
PHENOMENON An unusual optical effect displayed by a gem.
GROUPS A family of gems from several closely related mineral species.
NATURAL GEMS Gems produced by natural processes, without human help.
LAB-GROWN GEM A manmade (synthetic) gem with essentially the same chemical composition,
crystal structure, and properties as its natural counterpart.
FEDERAL TRADE COMMISSION A US government agency that issues guidelines for the jewelry
trade.
SELECTIVE ABSORPTION Process by which a material absorbs some components of visible light
and returns others.
HUE The first impression of an object's basic color.
TONE Degree of darkness or lightness of a color.
COLORED STONE Any gem material other than diamond.
GEMOLOGY The study of gems.
ORGANIC Once living, or produced by a living organism (plant or animal).
MINERALS A natural, inorganic substance with a characteristic chemical composition and usually
characteristic structure.
INORGANIC Composed of, or arising from, non-living matter.
CHEMICAL COMPOSITIONS Kinds and relative quantities of atoms that make up a material.
DURABILITY A gemstone's ability to withstand wear, heat, and chemicals.
LUSTER The appearance of a material's surface in reflected light.
TRANSPARENCY Degree to which a material allows light to pass through it.
HARDNESS How well a gemstone resists scratches and abrasion.
TOUGHNESS How well a gemstone resists breaking, chipping, and cracking.
STABILITY How well a gemstone resists the effects of light, heat, and chemicals.
CRYSTAL STRUCTURE Regular, repeating internal arrangement of atoms in a material.
, GIA COLORED STONE ESSENTIALS QUESTIONS AND CORRECT SOLUTIONS
CHEMICAL FORMULA Written description of a material's chemical makeup.
TRACE ELEMENTS Atoms in a gem that aren't part of its essential chemical composition.
AMORPHOUS Lacking a regular crystal structure.
SPECIES A broad gem category based on chemical composition and crystal structure.
VARIETY A subcategory of species based on color, transparency, or phenomenon.
PHENOMENON An unusual optical effect displayed by a gem.
GROUPS A family of gems from several closely related mineral species.
NATURAL GEMS Gems produced by natural processes, without human help.
LAB-GROWN GEM A manmade (synthetic) gem with essentially the same chemical composition,
crystal structure, and properties as its natural counterpart.
FEDERAL TRADE COMMISSION A US government agency that issues guidelines for the jewelry
trade.
SELECTIVE ABSORPTION Process by which a material absorbs some components of visible light
and returns others.
HUE The first impression of an object's basic color.
TONE Degree of darkness or lightness of a color.
