Calcite with Colorless Labradorite
This listing is for the exact specimen pictured.
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO3).
Over 800 forms of calcite crystals have been identified. Most common are scalenohedra.
Calcite is a common constituent of sedimentary rocks, limestone in particular, much of which is formed from the shells of dead marine organisms. Approximately 10% of sedimentary rock is limestone. It is the primary mineral in metamorphic marble. It also occurs in deposits from hot springs as a vein mineral; in caverns as stalactites and stalagmites; and in volcanic or mantle-derived rocks such as carbonatites, kimberlites, or rarely in peridotites.
Ancient Egyptians carved many items out of calcite, relating it to their goddess Bast, whose name contributed to the term alabaster because of the close association. Many other cultures have used the material for similar carved objects and applications.
Labradorite is a feldspar mineral first identified in Labrador, Canada which can display an iridescent effect. Labradorite is an intermediate to calcic member of the plagioclase series. It has an anorthite percentage of between 50 and 70. The specific gravity ranges from 2.68 to 2.72.