What is a Mineral About 3000 Mineral exist
What is a Mineral?
About 3000 Mineral exist in the Earth’s crust. However only about 30 of those minerals are common.
Defining Characteristics of a Mineral 1. Naturally Occurring 2. Inorganic 3. Solid 4. Specific Composition 5. Definite Crystal Structure
Naturally Occurring - formed by natural processes
Inorganic - not alive and never was alive
Solid - definite shape and volume
Specific Composition - has a molecular formula ex. Quartz Si. O 2
Definite Crystal Structure - atoms arranged in repeated patterns
Crystal - A solid in which the atoms are arranged in a repeating pattern
For a mineral to grow in a regular geometric shape it must grow at a slow even rate in a nonrestricted open space
For a mineral to grow with no particular shape it must grow at a fast uneven rate in a restricted space
Minerals Can Form From Magma & Solution
Magma - Molten materials found beneath the Earth’s surface
Minerals that will form from magma depends on the type of elements & amount of elements present
Size of Crystals is Dependent on Cooling Rate
Slow cooling from deep within Earth’s Interior produces large crystals Fast cooling near the surface produces small crystals
Solution - Homogeneous (same throughout) mixture whose components cannot be distinguished and can be classified as liquid, gaseous, solid, or a combination
PRECIPITATION crystals begin to precipitate (drop out) out of solution after a solution becomes supersaturated
Supersaturated - Overfilled
Liquid evaporating creates a supersaturated solution where the elements left behind begin to arrange into crystals
8 Most Common Elements in Earth’s Crust Oxygen (O) Calcium (Ca) Silicon (Si) Sodium (Na) Aluminum (Al) Magnesium (Mg) Iron (Fe) Potassium (K)
Silicates - Minerals containing Silicon and Oxygen
Silicates make up approximately 96% of the Minerals found in the Earth’s Crust
Silica Tetrahedron 3 -dimensional shape structured like a pyramid
O Si O O O Silica Tetrahedron
There are many combinations in which ions can bond with simple silica tetrahedron, this gives us our enormous diversity of silicate minerals
The Properties of are Minerals Determined by the INTERNAL ARRANGEMENT OF ATOMS
Carbonate minerals contain one or more metal elements + CO 3
Minerals made of a metal + oxygen atoms are called Oxides
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