GIA Colored Stones Exam 551-600

Question 1

The color of a sorting pad should be ___________ .

Answer 1

neutral

Question 2

Colored stones with higher value usually have what color characteristics?

Answer 2

medium to medium_dark tone and vivid saturation

Question 3

Amber is actually _____________ .

Answer 3

hardened tree resin

Question 4

Immature amber is known as _____________ .

Answer 4

copal

Question 5

What is the most valuable amber color?

Answer 5

red

Question 6

What type of coral is a calcium carbonate?

Answer 6

pink

Question 7

What is coral’s most valuable color?

Answer 7

red

Question 8

What are the two conchiolin coral colors?

Answer 8

black and golden

Question 9

What treatment can create a golden color from black coral?

Answer 9

bleaching

Question 10

What organic shows a structure called “engine turning” which looks like lines created on a lathe?

Answer 10

ivory

Question 11

What animal’s tusk produces the most valuable ivory?

Answer 11

elephant

Question 12

Paua is a Maori name for __________ .

Answer 12

albalone shell

Question 13

Tortise shell is composed of what?

Answer 13

protein

Question 14

Jet is an ornamental form of ___________ .

Answer 14

lignite coal

Question 15

What country is the major source for jet?

Answer 15

England

Question 16

Name a natural glass gem.

Answer 16

moldavite

Question 17

Where is the only source of benitoite located?

Answer 17

California

Question 18

What are the circular marks sometimes left in amber when treaters heat and oil it?

Answer 18

sun spangles

Question 19

How old does tree resin have to be before it is called amber?

Answer 19

1 million years old

Question 20

Nearly all trade in new elephant ivory has been illegal since what time period?

Answer 20

mid 1970’s

Question 21

What is the most difficult shape to produce in pearl culturing?

Answer 21

round

Question 22

What is the name of the largest gem_quality natural pearl?

Answer 22

Dudley

Question 23

Pearl colors are usually _________ .

Answer 23

low in saturation

Question 24

In the trade; Tahitian cultured perals witha dark green_gray to blue_gray bodycolor and rose’ to purple overtones are called ____________.

Answer 24

peacock

Question 25

What overtone color increases the value of akoya cultured pearl with white bodycolor?

Answer 25

rose'

Question 26

When mollusks live in cooler water; they form pearls with ___________ .

Answer 26

thicker nacre

Question 27

Pearls that show noticeable surface characteristics are considered ____________ blemished.

Answer 27

severely

Question 28

The best way to clean pearls is with ____________ .

Answer 28

warm; mild soapy water

Question 29

The nacre quality classification described as "Nucleus not noticeable; no chalky appearance" is classified as __________ .

Answer 29

acceptable

Question 30

The matching level that describes a group of pearls that have minor variations in uniformity is considered ____________ .

Answer 30

good

Question 31

Farmers of every cultured pearl type does this after harvest.

Answer 31

wash; dry; sort

Question 32

Almost all akoya and Chinese freshwater pearls are __________.

Answer 32

bleached

Question 33

Usually; the diameters of the cultured pearls in a hank vary from each other by nor more than how many millimeters?

Answer 33

0.5mm

Question 34

Essence d'orient is a mixture of ___________.

Answer 34

fish scales and varnish

Question 35

What happens when saltwater cultured pearls are exposed to gamma rays?

Answer 35

the bead nucleus darkens

Question 36

All pearls display bodycolor; and some also have what characteristics?

Answer 36

overtone; orient; both

Question 37

A pearl with one or more grooved ridged rings all the way around it is called a ___________.

Answer 37

circled pearl

Question 38

A mixture of clear varnish and fish scales used in making imitation pearls is called _________ .

Answer 38

essence d'orient

Question 39

A cultured pearl with a hole drilled all the way through; sometimes called drilled_through is called ___________.

Answer 39

full_drilled

Question 40

A cultured pearl with a hole drilled halfway through to permit mounting on a post is called ______________.

Answer 40

half drilled

Question 41

A procedure that includes cleaning buffing and sometimes bleaching; done to make cultured pearls presentable and appealing is called ___________.

Answer 41

process

Question 42

Blemishes or irregularities confined to a pearl's surface is called a ________ .

Answer 42

surface characteristic

Question 43

A cultured pearl with any unsightly potion cut or ground off is called a ____________.

Answer 43

three_quarter_cut

Question 44

Features used to judge the quality and value of pearls are called __________.

Answer 44

value factors

Question 45

Most gemstones form in the __________.

Answer 45

continental crust

Question 46

Rocks altered by heat and pressure are ___________.

Answer 46

metamorphic

Question 47

What gem can crystallize in volcanic rock from gasses released by magma?

Answer 47

Vietnamese ruby

Question 48

Where is the key locality for hydrothermal gems?

Answer 48

Ouro Preto; Brazil

Question 49

What gems form by metamorphism?

Answer 49

ruby; emerald; alexandrtie; tanzanite; tsavorite

Question 50

Heat and pressure transform limestone into ___________.

Answer 50

marble