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Geologynet: Rock Forming Minerals
Use the search to find information on rock forming minerals. Characteristics including formula, color, cleavage, and hardness are presented in an easy-to-read chart.
University of Oregon
Ask Geo Man: Igneous Rock Forming Minerals
Ask GeoMan lists Olivine, Pyroxene, Amphibole, Feldspar, Mica and Quartz, as five common rock forming minerals. Characteristics of each are also given.