CALCITE ON SPHALERITE

Sphalerite, a sulfide mineral represented by the chemical formula (Zn, Fe)S, serves as the principal ore for zinc extraction. This mineral occurs in various types of deposits, predominantly within sedimentary exhalative, Mississippi-Valley type, and volcanogenic massive sulfide formations. It is commonly associated with other minerals such as galena, chalcopyrite, pyrite, as well as calcite, dolomite, quartz, rhodochrosite, and fluorite.

Calcite is a carbonate mineral and the most stable form of calcium carbonate (CaCO3). It is widely found, especially as a key element in limestone. With a hardness rating of 3 on the Mohs scale, calcite is assessed based on its ability to be scratched. Large crystals of calcite are utilized in optical devices, while limestone, primarily made up of calcite, serves a variety of purposes.

This specimen has also miniature crystals and thousands of tiny calcite or dolomite crystals (white), and the matrix is a sulfide.