Calcite, Marcasite and Galena - Essay Example

Calcite is a mineral that is formed from the reaction of calcium and carbon to form(CaCo3), and occurs in granular or compact shapes, exhibiting a white color in pure form or grey, blue, black, red, yellow or orange if it has some impurities. Due to its carbon nature, it can easily be reacted or dissolved with most acids or water to release a carbon dioxide gas Its retrograde solution thus fairly soluble in hot water and subject to the favorable conditions of precipitations will give a cementing product to the apparent rock and a porosity on dissolution and its removal from the rock on dissolution.

The calcites are usually transparent or opaque and have traces of phosphorescence and/or fluorescence hence when used to view objects, they appear double. This is why its use for optical purposes.It occurs naturally owing to the marine decomposition of hard planktons like red algae, echinoderms, and sponges and it is found in limestone, volcanic, kimberlites, sedimentary or peridotites. It is used especially in the military for in gun sights. It has also agricultural uses like stabilization of soil and concrete repair.

Galena is the natural form of the mineral lead sulphide and is the main ore for both silver and lead. It is also called lead glances and distributed widely on the sulphide minerals. It is mainly used to make lead-acid batteries, lead sheets and shots.