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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

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.


Geology in the National Parks home \| U.S. Department of the Interior \| U.S. Geological Survey Privacy statement / General Disclaimer USGS Western Earth Surfaces Processes Team Webmaster http://geology.wr.usgs.gov/docs/usgsnps/index.html This page was last updated on 01/13/04

Common Rock-Forming Minerals and Their Elements

Type

Mineral family - composition

Light-Colored Silicates

Dark-Colored Silicates

Nonsilicates