Minerals

Minerals

By: Rabbi Goldberg

Introduction

• The lithosphere is made of one or more naturally formed materials called ROCK. – All Rocks are made up minerals

• Monominerelic – made up of one mineral

• Polymineralic- a rock made up of more than one mineral

One Mineral

Minerals

• Minerals – Are naturally occurring, inorganic crystalline

solid materials with definite chemical composition, structure, and specific physical properties

• Scientist have discovered over 2,400 minerals in the world.

• Around 12 of them make up 90% of all the rocks – These minerals are

nicknamed rockformers.

Characteristics of minerals in rocks

• Minerals can be made up of one element or more than more element

• The most abundant ( plenty of ) element is oxygen with silicon coming in #2

How can we tell what type of mineral were are looking at?

• Minerals are identified based upon physical and chemical properties – Color – Luster – Cleavage vs fracture – Streak – Crystal form – Etc…….

Color

• The outside color of the mineral can help identify very few minerals. – Such as

• Sulfur

• This is most minerals have more than one color and very few have a distinct color

Hardness

• Hardeness- is the resitence of a mineral being scratched – Hard mineral will make

a mark on a softer mineral

Hardness continued

• Moh’ Scale of Hardness – List 10 minerals from

soft to the hardest • #1 is talc with is the

softect mineral • #10 is diamonds which

is the hardest mineral

– By using this list we can determine which minerals will scratch the other

Hardness continued

• For example if a mineral cant scratch quartz but can scratch feldspar What number of harness is it?– Answer is ______

Streak

• Is the color of powder of a mineral when it is either crushed or scratched on on a streak plate – The color of the

mineral might be different then the color of the streak

Luster

• Luster – If you would look at the

mineral in light what type reflection would it give off

• It might shine like metal and therefore would have a metallic luster

OR

• it might not shine like metal and therefore would be called non metallic luster

Cleavage vs. Fracture

• Lets say I would break a mineral

• If the mineral breaks with smooth edges or surfaces it is said to have _______________

• If the mineral has jaggered or rough surface by the break then it is said to be _______________.

Crystal formation

• This depends on the atomic structure of the mineral – Is the mineral formed

under the amount of pressure

– Two mineral with similar properties can be distinguished by their crystal formation

Specific gravity

• The ratio of the weight of a mineral to equal volume of water – A mineral with specific

gravity 3.0 will be 3x heavier then the equal volume of water

– Specific gravity = density

Special Properties

• Some mineral have special properties – Calcite will bubble

carbon dioxide when dropped in hydrochloric acid

– Halite – tastes salty – Magnetite – is

magnetic

Mineral Properties

• Minerals are crystalline – The atoms inside are bonded

in a particular way • Two mineral with the same

chemical composition (make up) CAN HAVE DIFFERENT PROPERTIES

– Graphite and diamonds are both chemically made up the same materials

» Diamonds are under extreme pressure and therefore their crystalline composition is closer together and stronger than graphite