GIA Final exam colored stones Latest Update 2024-2025 Actual Exam 200+ Questions and 100% Verified Correct Answers Already Graded A+ Verified by Professor
"Marabá" amethyst is often - CORRECT ANSWER: less saturated in color than amethyst from other sources but color is uniform
A broad gem category based on chemical composition and crystal structure is a -
CORRECT ANSWER: gem species.
A carved design that projects slightly from a flat or curved surface is called a(n) -
CORRECT ANSWER: cameo
a cylindrical synthetic crystal produced by a melt process - CORRECT ANSWER: Boule
a distinct change in gem color under different types of lighting, color change most
common gems - CORRECT ANSWER: alexandrite
A gem colored by an element that's part of its basic chemistry is called - CORRECT
ANSWER: idiochromatic
a gem colored by trace elements in its crystal structure - CORRECT ANSWER:
allochromatic
a gemstone ability to tolerate the effects of light,changes in temperature or the action of
chemicals - CORRECT ANSWER: stability
a gemstone ability to withstand wear,heat and chemicals - CORRECT ANSWER:
durability 1 / 3
a gemstone resistance to breaking and chipping - CORRECT ANSWER: toughness
a gemstone resistance to scratches and abrasions,directly related to the strenght of the
chemicals bonds between its atoms - CORRECT ANSWER: hardness
A major source of black star sapphire is - CORRECT ANSWER: thailand
A metric carat equals - CORRECT ANSWER: 0.20 gram.
A natural, inorganic substance with a characteristic chemical composition and usually
characteristic crystal structure is a(n) - CORRECT ANSWER: mineral
a pattern of dark vertical lines or bands shown by certain gema when viewed through a
spectroscope - CORRECT ANSWER: absortion spectrum
A procedure that includes cleaning, buffing, and sometimes bleaching, done to make
cultured pearls presentable and appealing, is called - CORRECT ANSWER: Process
A quantity of stones of similar or mixed qualities, from a single mine or from various
sources, offered for sale together is called a - CORRECT ANSWER: parcel
A rainbow effect created when light is broken up into spectral hues by thin layers is -
CORRECT ANSWER: iridescense
a small defect in the crystal structure of a material that can absorb light and give rise to
a color - CORRECT ANSWER: color center
A snakeskin structural pattern is typical of - CORRECT ANSWER: synthetic opal.
- / 3
A special kind of interference phenomenon that produces patches of pure spectral
colors - CORRECT ANSWER: difraction
A substance that consists of atoms of only one kind is a - CORRECT ANSWER:
Chemicals element
A treatment that makes turquoise less porous without the use of polymers and improves
its ability to take a good polish is - CORRECT ANSWER: the Zachery method
A unit cell defines a mineral's - CORRECT ANSWER: basic identity.
Adularescence is caused by - CORRECT ANSWER: scattering of light
After irradiation, which gem's color is stable under normal wearing conditions? -
CORRECT ANSWER: Golden beryl
All garnets have essentially the same - CORRECT ANSWER: crystal structure
An angular, hollow space that resembles a mineral inclusion is called a - CORRECT
ANSWER: negative crystal
Aragonite is a crystallized form of - CORRECT ANSWER: calcium carbonate
Asterism in black star sapphire is caused by - CORRECT ANSWER: Hematite
Australian sapphire's blue color is often described as - CORRECT ANSWER: inky
Blue sapphire's most common crystal habit is a(n) - CORRECT ANSWER: spindle-
shaped hexagonal pyramid or bipyramid
- / 3