Mineral Classification
Minerals are naturally occurring, inorganic substances with a quantifiable chemical composition and a crystalline structure. For a substance to be classified as a mineral, it must be a solid (non-liquid). In addition to having a crystal structure. The term "mineral" refers to both a material's chemical composition, and its structure. The term "rock" should not be confused with the term "mineral." A rock is an aggregate amalgamation of one or more minerals, and can also contain organic substances. A rock can be composed of only one mineral or it can contain many minerals.
Substances that are "mineral-like" but don't meet this definition are classified as "mineraloids." Minerals range in composition from pure elements (carbon and metals) and simple salts to highly complex silicates (emeralds, tourmaline, etc.). According to the International Mineralogical Association, there are currently over 4,000 known minerals, which are categorized according to chemical composition or "mineral class." There are eight mineral classes which are categorized by anion (negative ion) group.
This minerals shown on this mineral classification chart are listed in the approximate order of their abundance within the Earth's crust, starting with the most abundant "silicate class."
1. Silicate Class
Nesosilicates
Sorosilicates
Cyclosilicates
Inosilicates
Phyllosilicates
Tectosilicates (framework silicates)
2. Carbonate Class
Carbonates with Hydroxyl or Halogen
3. Sulfate Class
Sulfur Oxides
4. Halide Class
Halogens
5. Oxide Class
Element in (IV) State
6. Sulfide Class
Sulfides
7. Phosphate Class
Phosphate Minerals
8. Element Class
Carbon Group
Native (Rare Earth) Metals
Gold Group
Platinum Group
Mineraloids Group
A "mineraloid" is a mineral-like substance that does not demonstrate crystallinity and who's chemical composition is beyond the accepted ranges for specific minerals. Pearls contain the mineral "calcium carbonate" but the structure is bonded together by organic materials. Obsidian is not a "crystal" but is instead amorphous-glass. Amber is a heterogeneous composite with a "gem-like" appearance, but consists of resinous bodies that are soluble in alcohol.
Non-Crystalline Minerals
Crystal Geometry Links
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