Common Minerals

To learn to identify minerals you really need to take an introductory geology lab. There is no substitute for hands-on experience. Even if you do take such a lab, do not be surprised if you still lack confidence in your ability to identify minerals. It just takes lots of practice. Remember: the more mineral samples you look at, the better you will get! This page is best used to review minerals that you have already studied in a lab.    Common Minerals in Igneous Rocks   There are only 8 minerals common in igneous rocks: potassium feldspar, quartz, plagioclase feldspar, amphibole ("hornblende"), muscovite, biotite, pyroxene ("augite"), and olivine. Hornblende is one specific mineral of the amphibole group. It is not normally possible to tell one dark amphibole mineral from another in hand-sample, but hornblende is so common it is frequently assumed to be the amphibole present. Similarly, augite is one type of pyroxene and is the most common pyroxene mineral encountered.    Common Minerals in Sedimentary Rocks   Sedimentary rocks are also dominated by a small number of minerals: Quartz, K-feldspar, and muscovite grains are frequently derived from older igneous or metamorphic rocks. Clay minerals, calcite, dolomite, halite, gypsum, and (in small but important quantities) pyrite form during mineral weathering while the rest normally precipitate from a watery solution. Common minerals in metamorphic rocks   Metamorphic rocks commonly contain many of the minerals previously listed (quartz, K-feldspar, plagioclase, muscovite, biotite, amphibole, calcite, dolomite) plus a few common ones that are distincitvely metamorphic: garnets, staurolite, kyanite, chlorite, serpentine.

Alphabetical List of Minerals amphibole (hornblende), biotite, calcite, chlorite, clay minerals (kaolinite), dolomite, garnet, gypsum, halite, K-feldspar, kyanite, muscovite, olivine, plagioclase, pyrite, pyroxene (augite), quartz, serpentine, staurolite

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