Gemstone (L6)

Question 1

What is the study of gems referred to as?

Answer 1

gemology

Question 2

Gemstone is a collective term for _____

Answer 2

all objects used with ornamental stones for personal adornment

Question 3

What is a “gem”

Answer 3

a gemstone that has bveen cut to show its beauty

Question 4

The 2 main categories of Gemstones?

Answer 4

Precious gemstones and Semiprecious gemstones

Question 5

What are the 3 qualities that the value of most gemstones (precious or semiprecious) are based on?

Answer 5

Beauty
Durability
Stability

Question 6

What is the quality “Beauty”

Answer 6

bsed on one or a combination of the qualities of color, lustre, transparency (or clarity), or enhanced optical properties due to cutting and fashioning

Question 7

What is the total breakdown of how the gemstone’s value is judged

Answer 7

50-60% quality of color
20-30% clarity
10-20% on the cut of the finished stone

Question 8

The 4 C’s used to determine the value of gems?

Answer 8

Carat weight, Color, Clarity, and Cut

Question 9

What does Durability refer to?

Answer 9

The resistance of a gemstone to damage

Question 10

What are2 of the main properties influencing the durability of a gemstone?

Answer 10

Hardness and Tenacity

Question 11

What is Tenacity?

Answer 11

the resistance to bending and breaking (diff from hardness)

Question 12

What does Stability refer to?

Answer 12

A gem’s resistance to destruction by chemical factors

or how well a gemstone retains its colour

Question 13

What are the 3 main additional factors influencing the value of a gemstone?

Answer 13

Weightr, Rarity, and Demand

Question 14

What standard unit of weight is used in the pricing of gemstones?

Answer 14

Carat (ct)

1 ct = 0.2 grams

Question 15

Where does the name Carat come from?

Answer 15

comes from the carob bean and in the old days, the weight of a gem would be measured equivalent to the weight of carob seeds

Question 16

What must you bear in mind when using the Carat measurement?

Answer 16

It must be applied within the particular gemston as the size of gem varys among different stones

Question 17

What should you use instead of carat weight when looking for the setting a particular gemstone?

Answer 17

the stone’s dimensions in mm

Question 18

What is the largest uncut diamond in the world?

Answer 18

Cullinan Diamond

Question 19

What was the largest stone cut from the original Culinan stone

Answer 19

Cullunan 1 (The Great Star of Africa)

Question 20

Where was the SECOND largest gem-grade diamond discovered?

Answer 20

Botswana

Question 21

What was the gem discovered in Botswana made into?

Answer 21

The Graff Lesedi Le Rona (largest emerald cut diamond in the world)

Question 22

What does “Rarity” refer to?

Answer 22

the exceptional nature of the natural geological processes that form them

Question 23

How can certain gemstone values fluctuate?

Answer 23

Depending on the trends in fashion

Question 24

Why was there misinformation regarding gems and their relationships?

Answer 24

because of the ancient practice of grouping precious stones by color rather than mineral makeup

Question 25

gemstone quality mineral of a single mineral can be given diff names if they are of diff color. T or F

Answer 25

T

Question 26

When corundum contains a sufficient quanitity of chromium, what happens and what is it called?

Answer 26

it exhibits a deep red color and is called “Ruby”

Question 27

When corrundum exhibits any color other than red, what is it called?

Answer 27

Sapphire

Question 28

What is Asterism and how is it created?

Answer 28

it is a star pattern in gems and results from the presence of the mineral rutile within the crystal

Question 29

What is emerald?

Answer 29

the green variety of beryl

Question 30

What is Aquamarine?

Answer 30

the light blue variety of beryl

Question 31

What are the 3 basic cuts used?

Answer 31

The Cabochon
The Brilliant Cut
The Step (Trap) Cut

Question 32

What is a Cabochon and where is it used in?

Answer 32

a cut that is basically a simple round-to oval shape

used in translucent (clouded) and opaque gemstones with bold colors and low-intermediate harndess

Question 33

Brilliant Cut? and what is it used for?

Answer 33

this round cut accentuates a gemstones ability to transmit, reflect, and disperse light, and used for diamonds

Question 34

The Step Cut and where is used?

Answer 34

has a broad table-like central facet surrounding by smaller and longer rectangular facets around its corners

emphasizes the color of the stones with a low degree of light dispersion

Question 35

The emerald cut and why is it used?

Answer 35

special type fo step cut, with the corners lopped off

developed to reduce edge damage of emeralds with a brittle tenacity