GEOLOGY & PLANETARY SCIENCE A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site mineral A selection of minerals. Credit: U.S. Geological Survey A naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal morphology, and physical properties such as density and hardness. Minerals are the fundamental units from which most rocks are made. Rocks, such as granite or sandstone, are mixtures of minerals. Their compositions can vary widely and cannot be approximated by a mineral formula. Moh's scale is used to calibrate the hardness of minerals. Related category    • GEOLOGY AND PLANETARY SCIENCE Source: U.S. Geological Survey Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP