MineralsMinerals

What is a mineral?What is a mineral?

5 Characteristics of a mineral5 Characteristics of a mineral Naturally OccurringNaturally Occurring Inorganic (Not Living)Inorganic (Not Living) Always a solidAlways a solid Has a definite chemical compositionHas a definite chemical composition Atoms are arranged in a repeating Atoms are arranged in a repeating

pattern (creates crystals)pattern (creates crystals)

Mineral IdentificationMineral Identification

Scientists identify Scientists identify mineral based on mineral based on their properties. their properties.

Color and Color and appearance are 2 appearance are 2 clues that we use to clues that we use to identify minerals. identify minerals.

Are color and Are color and appearance enough? appearance enough?

No WAY! No WAY!

HardnessHardness The measure of how easily a mineral can be The measure of how easily a mineral can be

scratched by other minerals. scratched by other minerals. To compare hardness a list of common minerals To compare hardness a list of common minerals

and their hardness was developed by Friedrich and their hardness was developed by Friedrich Mohs. Mohs.

We call is the Mohs scale. 1 = Softest, 10 = We call is the Mohs scale. 1 = Softest, 10 = Hardest. Hardest.

LusterLuster

Luster describes Luster describes how light is how light is reflected from a reflected from a minerals surface. minerals surface.

Luster is either Luster is either metallic (shiny and metallic (shiny and metal – like) or metal – like) or non-metallic (not non-metallic (not shiny) shiny)

ColorColor

The color of a mineral can serve The color of a mineral can serve as a clue to it’s identity. as a clue to it’s identity.

However, color is NOT enough to However, color is NOT enough to determine the identity of a determine the identity of a mineral. mineral.

Ex: QuartzEx: Quartz

StreakStreak Streak is the color of a Streak is the color of a

mineral when it is broken mineral when it is broken down into a powdered form. down into a powdered form.

When a mineral is rubbed When a mineral is rubbed across a Streak Plate, the across a Streak Plate, the mineral that is left behind is mineral that is left behind is powdered. powdered.

The streak test will only work The streak test will only work for minerals that are softer for minerals that are softer than the streak plate. than the streak plate.

Why? Why?

Cleavage and FractureCleavage and Fracture Cleavage is a Cleavage is a

property that property that minerals have when minerals have when they break along they break along smooth, flat surfaces. smooth, flat surfaces.

Fracture is a property Fracture is a property that minerals have that minerals have when they break when they break along rough, jagged along rough, jagged surfaces. surfaces.

Other PropertiesOther Properties

Some minerals are Some minerals are magnetic (Ex: magnetic (Ex: Magnetite)Magnetite)

Some minerals fizz Some minerals fizz when they come in when they come in contact with an acid. contact with an acid. (Ex: Calcite)(Ex: Calcite)

Video Clip Video Clip QuestionsQuestions

1.1. How many minerals found in How many minerals found in nature?nature?

2.2. About how many are About how many are important in developing rocks?important in developing rocks?

3.3. How many properties tests are How many properties tests are used to identify minerals?used to identify minerals?

4.4. Which is more dense? Which is more dense? Nonmetal base or metal base?Nonmetal base or metal base?