Minerals and Their Uses

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Minerals and Their Uses
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Minerals You Know

• Can you think of some different types of
  minerals?
• Blue Sapphires
• Red Rubies
• Green Emeralds
• Mineral Graphite (in pencil lead)
• Mineral Copper (used in coins)

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Defining Minerals

• There are four conditions that
• define minerals.

• Minerals occur naturally
• Salt deposits formed naturally is the mineral
  halite. Salt that we use to flavor food or NaCl
  is not a mineral

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1. Minerals are inorganic solids.

• They are not alive or formed by anything that was
  alive.

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• Minerals have unique chemical compositions.
• Each type of mineral has a chemical composition
  that is unique to that mineral. For example
  mineral quartz is a combo of two elements, Si and
  O. Other minerals may contain silicon and oxygen
  but the arrangement and proportion
• of these elements in quartz
• are unique to quartz.

Quartzs Chemical Formula SiO2
Topazs Chemical Formula Al2F2SiO4
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• Minerals have crystalline structure.
• Atoms in a mineral are arranged in a regular
  geometric pattern repeated over and over again.

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Gems

• Some minerals are gems
• or also know as a highly priced mineral that is
  rare, or difficult to obtain
• What is place that is known for its gems?
• A pharaohs treasures are easily known as gems
  because they have been cut and polished. If they
  were not cut and polished would you know what to
  look for?

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Identifying Minerals

• What was the California Gold Rush?

This was a time in history when people left their
homes and families and went in search for their
fortunes. It was a massive migration of people
to an area where gold was
discovered. It started in Sutters Mill in
California in 1848. If you were alive then would
you have been apart of it, if so would you know
what to look for?
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Can You Tell the Difference?

• One of these pictures is gold the other is not
  can you tell the difference?

If you guessed this one give yourself a pat on
the back, youre right
Haha Fooled You
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Identifying Minerals

• We use five characteristic to identify minerals

1. Streak
2. Color
3. Luster
4. Hardness
5. Cleavage and fracture

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Streak

• When a mineral is rubbed across a streak plate, a
  streak is left behind.
• The color of a mineral when it is broken up and
  powdered is called its streak.

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Color

• Color of a mineral can help to identify what it
  is, however you do need more information. Some
  minerals that are easy to identify by color
  include sulfur and azurite.

?Sulfur
Azurite ?
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Luster

• Luster refers to the way that a mineral reflects
  light. Minerals are divided into to groups based
  on their luster, Nonmetallic Luster and Metallic
  Luster

Feldspar Mineral-Nonmetallic Luster
Pyrite Mineral-metallic luster
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Hardness

• The color, luster, or streak can vary among
  samples of mineral. Hardness is a more useful
  property to help identify different minerals.
• Hardness is a measure of how easily a mineral can
  be scratched.
• We use the Mohs Scale, named after Friedrich Mohs
  who devised it.

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Mohs Scale

• Starts at 1 with Talc which is easily scratched
  with your nail moves to 2 and Gypsum that can be
  scratched with your nail at 3 there is Calcite
  that can barely be scratched with your finger.
  It ends at 10 with the diamond that scratches
  common materials and is often used to sharpen
  knifes.

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Cleavage and Fracture

• Minerals differ in the way they break.
• Minerals that break along a
• smooth, flat surfaces have
• cleavage.
• Example- Mica
• Minerals that have curved,
• rough, or jagged surfaces
• when they break apart have
• fracture.
• Example- Quartz

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Mineral Formation

• There are two main ways that minerals form.
• One is the cooling of magma- when magma cools
  elements in the magma may form minerals
• The other is formed from elements dissolved in
  liquid-When the liquid evaporates the elements
  stay behind and may form minerals

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Minerals Form from Cooling Magma

• Magma is the hot, molten core beneath Earths
  crust. It is made up of the same elements and
  compounds that make up minerals.
• When the magma is forced
• up it cools.
• Once cooled the elements
• in the magma may
• combine chemically and
• form minerals.

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Slow or Quick

• This cooling process can happen quickly or
  slowly.
• If magma cools slowly it form large crystals.
• Mica, feldspar, and quartz have large crystals

• If magma cools quickly minerals form small
  crystals. This happens when magma reaches
  Earths surface because it is exposed to air and
  sometimes water.

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Minerals Form from Water Solution

• Many minerals are made of more than one element.
  Before they become minerals they are in liquid
  solution.
• When the water evaporates the elements may
  combine in a minerals characteristic crystal
  structure.