Mineral crystals form through the process of atoms bonding together in an orderly structure. There are three main ways minerals form: (1) from precipitation in hot water as the solution cools and atoms bond, (2) from magma as it cools below the solidification point of different minerals and they crystallize out, and (3) through evaporation of water leaving behind mineral deposits. The rate of crystal growth depends on temperature, pressure, and the atoms available in the surrounding environment.

1. Mineral
Formation
Mr. Thompson's Earth Science Class

2. Mineral
Formation
Mr. Thompson's Earth Science Class

3. Mineral Formation
• Mineral crystals
grow as atoms are
added to its
surfaces, edges,
or corners
QuickTime™ and a
decompressor
are needed to see this picture.
Mr. Thompson's Earth Science Class

4. Mineral Formation
• Growth depends on:
1) What atoms are available in the
surrounding area
2) How fast atoms can migrate to the crystal
3) Temperature and Pressure conditions of
the surrounding area
• Slower cooling allows for bigger crystals
• Different minerals crystallize from the same solution at
different temperatures.
• Pressure conditions have to be right for mineral
formation
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5. Mineral Formation
• Minerals can form in
various places
1) Precipitation in hot
water
-a solid forming in the
water
1) From magma cooling
2) From evaporation of water QuickTim e™ and a
decompressor
are needed to see this picture.
Mr. Thompson's Earth Science Class

6. Minerals from Hot Water
• Some minerals are made from hot-
water solutions that are rich in
dissolved mineral matter
• Example: Sugar will dissolve faster in
hot water, but when the water cools, the
sugar crystals will form again
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7. Minerals from Hot Water
This is one of the principles
of crystallization: as the
temperature of a liquid
drops, the amount of solid
ingredients it can hold in
suspension drops as well.
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8. Minerals from Hot Water
• As the hot water cools,
the atoms slow down
and the atoms within
can then form bonds
• Minerals will often form
around the edges of hot
springs where the water
is cooler
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9. Minerals from Hot Water
Minerals also form in cracks of rocks where the
water is cooler from the surrounding rock
-Cracks in rock become lined with mineral matter
Ex: veins can be found within rocks of
concentrated minerals like gold, silver, or
copper
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10. Minerals from Magma
• Magma = molten
rock found within
the Earth
• As magma cools the
atoms begin to
arrange into an
orderly structure QuickTime™ and a
decompressor
are needed to see this picture.
Mr. Thompson's Earth Science Class

11. Minerals from Magma
• When the temperature
of magma drops below
the “solidification
temperature” of a
specific mineral, the
crystals will begin to
grow
Mr. Thompson's Earth Science Class

12. Minerals from Evaporation
• Minerals can form from
water on the Earth’s
surface
• When water evaporated
from solutions rich in
minerals, the minerals
are left behind when the
water is gone
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13. The End
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