Sphalerite

Sphalerite is an unusual rare gemstone which is craved for by people as it possesses more brilliance than diamonds. It gets its name from the Greek word which means “unfaithful rock”, which was given in the year 1847 by E. F. Glocker .It has another name which is “Blende”. Its chemical name is Zinc Iron Sulfide. Sphalerite comes in a whole gamut of colors which are yellow, white, reddish-brown and black. The casual names given to Sphalerite are:

Black Jack
Red Ruby.

Sphalerite is a unique mineral stone that has cleavage in 6 directions. The rhombic dodecahedronic structure makes it exceptional. Miners face a lot of problem while mining this gemstone as it is repeatedly confused with minerals like tetrahedrite, galena and acanthite. Sometimes it shows striations. Pure forms of Sphalerite are white but the presence of impurities give it a brownish streak.

It has a property called “triboluminescence” according to which Sphalerite discharges orange light when it is knocked with some hard material. It forms a polymorph with the minerals Wurtzite and Matraite. The structure of Sphalerite shows similarity with that of diamond. The luster of this gemstone can be earthy, adamantine or slightly metallic.

The places where Sphalerite is found are:

Missouri, Illinois, Tennessee in USA.
Broken Hill in Australia.
Germany
Morocco
Burma
Peru
England
The transparent varieties are available only in Mexico and Spain

Sphalerite has a high refractive index and excellent luster which make it desirable.

The uses of Sphalerite:

Industrially, this gemstone acts as an essential ore of Zinc.
As it is soft, it is not usually cut as gemstones but forms a part of any collector's edition.
It becomes a major ore of those metals which are present as impurities in it.