MineralsMinerals are all around us

Today you will learn

Fascinating FactThe elements oxygen, silicon, aluminum, iron, magnesium, calcium, potassium, and sodium make up 75 percent of all minerals on Earth.

•What the characteristics of minerals are

•How minerals are classified into groups

•Which mineral group is most common

Just a box of rocks

BACKGROUND:  Scientists have identified over 2000 different minerals in the earth's crust. 75% of the earth's crust is composed of about a dozen different rock-forming minerals. The rocks composed of these minerals can be formed in three different ways. Scientists can learn many different things about a rock by observing and classifying it.

What is a mineral?

Naturally occurring solid formed from elements or compounds in Earth’s crust

All minerals are inorganic

Minerals are the building blocks of rocks

What is a mineral?

A mineral may be an element or a compound

Mineral Formula

Gold Au

Silver Ag

Copper Cu

Quartz SiO2

Galena PbS

Metal Minerals

Aluminum, iron, copper, and silver are examples of metal minerals

Recovered for use are called mineral resources

Useful- stretched into wire, flattened into sheets, hammered

Figure 2-14 pg. 47

Mineral characteristic #1

occurs naturally not artificial or man-made

Mineral characteristic #2

Solidnot a liquid or a gas

Platinum

(It might take two billion tons of ore to produce one pound of platinum!)

Mineral characteristic #3

Definite chemical composition

Some minerals like gold or silver are made of only one element.

Other minerals, like quartz and calcite, are combinations of two or more elements.

Mineral characteristic #4

atoms arranged in an orderly pattern Minerals are usually solid crystals. They have a number of flat surfaces in an orderly arrangement. For example, a crystal of quartz is always hexagonal because of the way the atoms of silicon and oxygen join together.

Mineral characteristic #5

Inorganic - not alive and never alive

SNIFE

SolidNot Liquid or Gas or Plasma

Naturally OccurringNot Human-Made

InorganicNot Alive - Never Was

Fixed CompositionSame Recipe, Everywhere, Every Time

Element or CompoundNot a Mixture

Identifying Minerals

Physical properties- characteristics that can be observed or measured

Describe the physical properties of iron.

Other physical properties- color, streak, luster, hardness

Color and Streak

Many minerals are the same color

Some are more than one colorEx. Quartz- purple, yellow, pink, or colorless

Malachite is always greenAzurite is always blue

Streak

Streak- color of the powder left by a mineral

Streak of a mineral will always be the same for that mineral

Chalk is made from the mineral calciteLeaves a white powder behindCaCO3

Luster

The way a mineral’s surface reflects light

Metallic or nonmetallic luster

Metallic will shine like new coins

Nonmetallic will look waxy, glassy, or dull

Hardness

Hardness- relates to how much it resists being scratched

Moh’s scale ranks ten minerals in hardness

High number can scratch any mineral that has a low numberLower number cannot scratch a mineral with a higher number

Moh’s Hardness Scale