what is a mineral? naturally occurring inorganic solid specific chemical composition definite...
Post on 15-Jan-2016
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What is a mineral?Naturally occurringInorganicSolidSpecific chemical compositionDefinite crystalline structure
Specific chemical compositionEach mineral has a unique “recipe”
Quartz = SiO2
Calcite = CaCO3
Some minerals consist of a single elementCopper (Cu), Silver (Ag), Sulfur (S)
Definite Crystalline StructureAtoms are arranged in a regular geometric
patternPattern is repeatingMinerals that form in an open space may
grow into a single, large, well-defined crystalThis is rareMost crystals form in a restricted space so
their internal structure is not as obvious
Formation of mineralsFrom Magma
Magma cools as it rises toward the surface of the Earth
Compounds in the magma begin to interact chemically
Magma cooling slowly results in LARGER crystal sizes
Magma cooling very quickly results in SMALLER crystal sizes
Formation of MineralsFrom solution
When a solution cannot dissolve anymore of a substance it is considered supersaturated
This may cause mineral crystals to precipitate out of the solution
The same can happen if the liquid evaporates
Mineral GroupsNumbers
Approximately 3000 known mineralsAbout 30 are considered common10 make up 90% of the Earth’s crust
Oxygen, silicon, aluminum, iron, calcium, sodium, potassium, magnesium
SilicatesConsist of 1 silicon atom, 4 oxygen atoms and
usually one or more other elementsStructure is called a tetrahedron. (pyramid)Oxygen atoms can bond with one another in
several different waysExample – Olivine – Mg2SiO4
CarbonatesConsist of one or more metallic elements and
a carbonate group CO3Example – Calcite – CaCO3Carbonates are the primary minerals found in
limestone and marble
OxidesCompounds of oxygen and a metalExamples – hematite and magnetite FeO3Both are common and good sources of iron
HalidesMade up of Chloride and Fluoride along with
Calcium, Sodium, or PotassiumExample – Halite – NaCl (salt)