Minerals have many uses in Industry

Copper

Technology

Industry

Arts

Minerals have many uses in Industry

• Metals for cars and airplanes• Quartz and feldspar for glass• Fluorite and calcite for

toothpaste• Silver compounds for

photographic film• Mica and talc for painthttp://dsc.discovery.com/videos/howstuffworks-the-power-

of-lead.html

These are just a few ways we depend on minerals.

Minerals have many uses in Art

• Gemstone or birth stone – when first mined, gems are

often rough and dull– a jeweler will shape them

and set them into jewelry – material used to shape and

polish gemstones must be as hard the gemstone itself.

• Gold and silver

– also used in jewelry other decorative arts

– Both combine with copper to increase hardness

Minerals are formed in several ways

Molten

Rock Cools

Heat and Pressure

Organisms produce minerals

Hot Water

Cools

Water Evaporates

How Minerals

Are Formed

Minerals are formed in several ways

Water Evaporates

• Water usually has substances

dissolved in it. – Minerals can form when the water is

dissolved, leaving crystals behind.

Minerals are formed in several ways

Hot Water Cools• As the hot water moves through the Earth it

collects minerals. • That hot water cools and the minerals become

solid again.– This process can move a mineral from one area of the

Earth to another.

Minerals are formed in several ways

Molten Rock Cools• Magma

– molten rock inside the Earth contains all types of atoms that are found in minerals.

– as magma cools it hardens becoming solid

• Lava– is molten rock, with minerals in it that has reached the

earth's surface– Quartz is a mineral that crystallizes from

magma and lava

Minerals are formed in several ways

Heat and Pressure Cause Changes

• Heat and pressure cause new minerals to form as bonds between atoms break and new ones are created– At high temperatures carbon forms graphite

Minerals are formed in several ways

Organisms produce minerals• A few minerals are produced by living things

– Oysters and clams produce calcite and other carbonate minerals to form their shells.

– Humans produce apatite in our bones and teeth.

Many Minerals are Mined

• Minerals are found at Earth’s surface and deep below the Earth

• Most Minerals are combined with rockOres – Rocks that contain enough mineral to

be mined for profit

Many Minerals are Mined

Surface Mining• Minerals at or near Earth's surface are

recovered by surface mining.

• The soil and rock covering the mineral deposits are removed.PanningOpen-PitStrip

Many Minerals are Mined

Panning- minerals build up in riverbeds

as less dense minerals are carried away by the water+Goldhttp://www.bbc.co.uk/news/world-europe-11808349

Open pit mining- Extracting rock or minerals from the

earth by their deduction from an open pit or borrows+Coal, copper, gold, gravel, sand, marble

Many Minerals are Mined

Strip mining – miners strip away plants, soil and

unwanted rocks from the surface to reach the minerals.+Coal

Many Minerals are MinedDeep mining

– Used when ores are far below the Earth's surface

– Miners create an underground cave system to reach precious metals (ores)+Coal, copper

http://dsc.discovery.com/videos/howstuffworks-dry-salt-mining.html

Many Minerals are Mined

• Mining can disrupt land, air, and water systems. Because of this, there are many laws governing mining.

• Any estimation of the cost of mining must include the costs of exploration, excavation, environmental production during mining, and environmental reclamation afterward.

• These costs must be weighed against the benefits of minerals.

• http://www.treehugger.com/files/2010/01/scientists-say-mountaintop-removal-mining-should-be-banned.php

• http://video.planetgreen.discovery.com/work-connect/focus-earth-mountain-minefield.html

• http://www.nytimes.com/2009/01/07/us/07sludge.html?_r=2&ref=us&pagewanted=all

• http://video.yahoo.com/watch/4342050/11659002

Properties of Minerals

• We identify different minerals by certain properties they contain:– Color– Streak– Luster– Density– Hardness– How they break = Fracture or Cleavage

Color• Minerals are colored because certain wave lengths of

light are absorbed, and the color results from a combination of those wave lengths that reach the eye.

• For some minerals, color is directly related to one of the major elements and can be characteristic and serve as a means of identification.

• The color of a mineral is the first thing most people notice. But it can also be the least useful in identifying a mineral. Most minerals occur in more than one color. Ex: Fluorite can be clear, white, yellow, blue, purple, or

green.

Color• Examples:

– Malichite is always green

– Azurite is always blue

– Rhodonite is always red or pink.

Streak• The streak of a mineral is the color of the

powder left on a streak plate when the mineral is scraped across it. – Streak Plate = piece of unglazed porcelain

• Only good for minerals with Hardness >7– The streak plate has a hardness of glass, so minerals

with a Mohs Hardness >7 will scratch the streak plate and won't powder the mineral.

• Streak can be useful for identifying metallic and earthy minerals. – Nonmetallic minerals usually give a white streak

because they are very light-colored.

Streak• Many minerals have very distinctive

streaks – Hematite always gives a reddish brown streak

no matter what type of luster it displays.– Limonite has a yellow to brown streak– Graphite has a black streak (graphite is in

your pencils!)

Luster• How light is reflected from the surface of a mineral.

• The two main types of luster:– Metallic = shiny like metal– Nonmetallic

• Types of nonmetallic luster:Vitreous: The luster of glass. Resinous: The luster of resin. Pearly: The luster of pearls. Greasy: Looks like it is covered in a thin layer of oil. Silky: The luster of silk. Adamantine: A hard, brilliant luster. Translucent: You can see into the mineral, but not completely

through it. Transparent: Transmits light completely through it, resembling glass.

LusterVitreous - Quartz

MetallicGold Pyrite

AdamantineZircon (cubic zirconium) DiamondResinous - Amber Pearly - Talc

Greasy - Chrysocolla

Silky - Malachite

Hardness• The hardness of a mineral is its ability to resist

scratching.

• The hardest mineral known, diamond, was assigned the number 10.

• Mohs Hardness Scale ranks the order of hardness Examples:

• Your fingernail can scratch the minerals talc and gypsum, with a hardness of 2 or lower.

• A copper penny can scratch calcite, gypsum, and talc.• A common misunderstanding of how to identify a

diamond is that it will scratch glass. While this is true, other minerals can scratch glass, too, as long as they have a hardness >6.

Hardness: Mohs Scale

Density (Specific Gravity)

• How many times more the mineral weighs compared to an equal amount of water (SG 1).

• How hefty a specimen feels has to do with how dense it is, its mass compared to its volume

Cleavage

• Cleavage is when a mineral breaks with smooth flat surfaces

• Cleavage can be described as perfect, good, imperfect, poor.

Fracture

• Fracture is when a mineral breaks, but the surface is not regular, does not show cleavage

Other PropertiesFluorescence Magnetism

Effervesce (fizz) with lemon juice or HCLEx: Calcite will fizz in lemon juice

SmellEx: Sulfer smells like rotten eggs

TasteEx: Halite tastes salty