GIA Colored Stones Exam 101-150

Question 1

Bluish_green to green.

Answer 1

Finest Emerald

Question 2

What element increases the amount of blue in an emerald’s color?

Answer 2

Iron

Question 3

The trade term “Zambian” describes emeralds with ________________ and ______________ than Columbian.

Answer 3

More bluish color and darker tone

Question 4

What type source rock are Brazilian emeralds mined from?

Answer 4

Pegmatites; where they intersect with schists.

Question 5

To emphasize the most desirable color; cutters orient a fashioned emerald with it’s table _____________ .

Answer 5

Perpendicular to the crystal length

Question 6

What is the estimated percentage of fashioned emeralds that contain filled fractures?

Answer 6

90% or more

Question 7

What to countries account for about 75% of emerald purchases worldwide?

Answer 7

US and Japan

Question 8

Four major emerald sources are Columbia; Zambia; Brazil and _____________ .

Answer 8

Zimbabwe

Question 9

One of Columbia’s traditional emerald mines is called ____________ .

Answer 9

Coscuez

Question 10

Compared to emerald’s from other sources; emeralds from African mines generally contain ____________ .

Answer 10

Fewer fractures.

Question 11

Emerald is a variety of what species?

Answer 11

Beryl

Question 12

What coloring of the stone disqualifies it from being considered and emerald.

Answer 12

Too yellowish or too bluish

Question 13

Name the two most common clarity characteristics in an emerald.

Answer 13

Fractures and liquid inclusions

Question 14

What does the trade term “jardin” mean?

Answer 14

jardin _ French word for garden. A descriptive term for an emerald’s inclusions that look mossy or garden_like.

Question 15

Natural emerald with colorless or colored filling.

Answer 15

Level 1 Treatment

Question 16

Natural emerald having filling that is minor; moderate or significant.

Answer 16

Level 2 Treatment

Question 17

Type of filler (upon request) if the laboratory is equipped.

Answer 17

Type 3

Question 18

Does the GIA provide Level 3 emerald treatment identification?

Answer 18

No.

Question 19

What is the name for an emerald in which it’s inclusions form a star_like pattern of rays.

Answer 19

Trapiche

Question 20

What are the three signs that point to an “emerald” being a glass immitation?

Answer 20

Gas bubbles; Concave Surfaces; Rounded facet junctions

Question 21

Reddish orange to orange red.

Answer 21

Imperial topaz

Question 22

The most valuable topaz varieties are _____________ .

Answer 22

Pink; Red

Question 23

Most gem_quality topaz comes from what growth source?

Answer 23

Pegmatites.

Question 24

The term precious topaz is used for ___________ .

Answer 24

Yellow to orange stones.

Question 25

What is the most common color of untreated; natural topaz?

Answer 25

Colorless.

Question 26

Wah Wah mountain area.

Answer 26

Imperial topaz source

Question 27

In order to obtain a treated pink color; yellow to reddish brown topaz must contain elemant

Answer 27

Chromium

Question 28

Medium dark blue to slightly greenish blue.

Answer 28

Finest Aquamarine

Question 29

Which method is used to produce synthetic aquamarine?

Answer 29

Hydrothermal

Question 30

The most important source country for aquamarine is ____________ .

Answer 30

Brazil

Question 31

Which recent source is the leading producer of small; commercial_quality aquamarine?

Answer 31

China

Question 32

Most aquamarine has it's color improved by what treatment?

Answer 32

Heat

Question 33

What color is morganite beryl?

Answer 33

Pink

Question 34

What gemstone is the rarest beryl?

Answer 34

Red beryl

Question 35

What color is morganite beryl?

Answer 35

pink

Question 36

The only source of red beryl is located in what US state?

Answer 36

Utah

Question 37

What causes the wide variety of colors in topaz?

Answer 37

Color centers and chromium.

Question 38

Why does topaz require special care and handling?

Answer 38

Cleavage.

Question 39

What area in Brazil is the world's major commercial source of imperial and red topaz.

Answer 39

Ouro Preto

Question 40

Which treatments are involved with topaz?

Answer 40

Heating and irradiation

Question 41

What are the two most important considerations for buyers of treated blue topaz?

Answer 41

Price and uniformity

Question 42

The finest most saturated color of aquamarine is normally shown in ____________ .

Answer 42

Large sizes.

Question 43

What three countries are the leading producers of aquamarine?

Answer 43

Brazil; Pakistan; China

Question 44

What trace element causes red beryls color?

Answer 44

Manganese

Question 45

What distinguishes green beryl from emerald?

Answer 45

Tone and saturation

Question 46

Because of topaz's elongation; how are they cut?

Answer 46

long ovals; pears; emerald

Question 47

What is the trade term for a highly prized; vivid blue adularescence displayed for the finest moonstone?

Answer 47

Blue sheen

Question 48

Tiny tension cracks in moonstone that iterfere with adularescence and reduce value are called _______ .

Answer 48

Centipedes

Question 49

What is the trade term for an imitation of aventurine feldspar made of glass that contains copper crystals?

Answer 49

Goldstone

Question 50

Why does feldspar; spodumene and diopside have weak consumer recognition?

Answer 50

Because of unpredictable supplies