Chocolate Calcite Bookends, PakistanCalcite is one of the most common minerals which grows in a wide variety of different shapes, colors and translucencies. The mineral itself actually belongs to a calcite group of "related carbonates" that are "isomorphous" with each other. All members of the group crystalize in triangular formations, have perfect rhombohedron cleavages, and in transparent rhombohedrons, display strong double refractions. Aragonite and Calcite are similar in chemical