Questionaire 1

All minerals are

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Which of these is an example of an organic gem?

Amber. -Amber comes from a living substance- the fossilized resin of trees that lived millions of years ago.

Minerals that do not have a regular crystal structure are

Amorphous. - Amorphous materials have no orderly internal structure. Amorphous gems include opal and volcanic glass.

A gem's variety is most often based on its

Color. -Color is the most obvious indicator of a gem's variety. Even though they're both beryl, aquamarine (blue) and emerald (green) have different variety names.

One of the most obvious effects of a trace element in a mineral is

Color. -When they're present, trace elements replace a few of the atoms, that usually make up a gem's chemical composition. For example, when chromium replaces some of the atoms in corundum, it's red which makes it a ruby.

The regular, repeating internal arrangement of atoms in a material is called

Crystal structure. -Crystal structure describes the way the atoms in a material are arranged.

A gem that is not easily scratched has good

Hardness. -The harder a gem is, the more it resists being scratched by other materials. Hardness is one component of durability.

The appearance of a material's surface in reflected light is called

Luster. -Luster plays a key role in a gem's visual appeal, or beauty.

A material that is structured so that no light can pass through is

Opaque. -A brick wall is a good example of an opaque material.

Gems that come from plants and animals are called

Organics. -Organic gems come from living organisms. Besides amber, other organic gems are pearls, coral, and ivory.

A gem that is not easily affected by light, chemicals, or heat has good

Stability. - Stability is the third component of durability. Gems that are vulnerable to certain chemicals, for example, shouldn't be cleaned with some solutions.

Which of the following terms should you use in a sales presentation to describe a manmade emerald?

Synthetic emerald/ Lab created. -You should never use the word "gem" or a gem name alone to describe a manmade gem material.

A gem's resistance to chipping is called

Toughness. - If a gem withstands breaking and chipping, it's very tough. Toughness is another component of durability.

The types and relative quantities of the atoms in a mineral make up its

Chemical Composition. - Chemical composition is like a recipe that describes the types and relative quantities of atoms in a substance.

All members of a gemological species have essentially the same

Chemical Compostition. - An example of a species is corundum, which includes the varieties ruby and sapphire.