Crystals

Geologists

Found in minerals and have a regular geometric

shape.

Scientist who study rocks and minerals to

help us learn about the formation of the earth.

Granite

Hardness

Rock composed of the minerals: Quartz, Mica,

and Feldspar.

How resistant a mineral is to being scratched.

Igneous rocks

Luster

Formed from minerals that have melted deep within

the Earth.

The way a mineral reflects light.

Magnetic minerals

Metamorphic rocks

Minerals which show magnetic properties. Two examples are

magnetite and hematite.

Formed from igneous, sedimentary, or other

metamorphic rocks which contain minerals that have

been changed by heat, pressure, or chemical

action.

Mineral

Mohs Scale

Occur in nature and have definite chemical

compositions and physical properties. They are the raw materials of rocks.

Used by geologists to classify a given mineral’s

hardness.

Rock

Scratch test

Earth materials made up of different

kinds of minerals.

Used to determine the hardness of a mineral.

Sedimentary rocks

Streak color

Formed as particles settle to the bottom of oceans and

lakes.

When an unknown mineral is rubbed against a streak plate, (unglazed piece of porcelain)

it may produce a colored line if it is softer than the streak

plate.

Streak plate

Unglazed porcelain material that is used to determine

the streak color of a mineral by rubbing a mineral over its

surface.