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Common Rock-Forming Minerals and Their Elements

Type

Mineral family - composition

Light-Colored Silicates

Quartz - silicon dioxide or silica

 

Feldspar - silicon tetroxide plus varying amounts of aluminum, sodium, calcium, and potassium

Dark-Colored Silicates

Mica - silicon tetroxide plus varying amounts of aluminum, postassium, iron, magnesium, calcium, sodium, and water

 

Pyroxene - silicon tetroxide plus varying amounts of aluminum, iron, magnesium, calcium, and sodium

 

Amphibole - silicon tetroxide plus varying amounts of aluminum, iron, magnesium, calcium, sodium and water

 

Olivine - silicon tetroxide plus varying amounts of iron and magnesium

Nonsilicates

Calcite - calcium carbonate

Of the seven abundant minerals, feldspars, micas, pyroxenes, amphiboles, and olivines are really mineral families, with a variety of named members. We mention other important mineral families on other pages.

Minerals are crystalline substances, meaning that the atoms of their constituent elements are arranged in a definite geometric structure. This structure gives minerals specific physical properties, which geologists, and everyone else for that matter, can identify in the field. Click on mineral names to see images.

North Cascades Minerals And Rocks
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Material in this site has been adapted from a book, Geology of the North Cascades: A Mountain Mosaic by R. Tabor and R. Haugerud, of the USGS, with drawings by Anne Crowder. It is published by The Mountaineers, Seattle.

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