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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