A few elements like carbon, sulphur, gold and noble gases, occur in free state while others are found in combined forms in the earth’s crust. Elements vary in abundance. Among metals, aluminium is the most abundant. In fact, it is the third most abundant element in earth’s crust (8.3% approx. by weight). It is a major component of many igneous minerals including mica and clays. Many gemstones are impure forms of Al₂O₃. For example, gems ‘ruby’ and ‘sapphire’ have Cr and Co respectively as impurity. Iron is the second most abundant metal in the earth’s crust. It forms a variety of compounds and their various uses make it a very important element. It is one of the essential elements in biological systems as well.

For obtaining a particular metal, first we look for minerals which are naturally occurring chemical substances in the earth’s crust and are obtained through mining. Out of many minerals in which a metal may be found, only a few are viable to be used as source of that metal. Such minerals are known as ores.

What is the formula of Sphalerite?

ZnS

The correct answer is option 2. ZnS.

Sphalerite is a mineral composed of zinc sulfide \((ZnS)\). It is the primary ore of zinc and is commonly found in hydrothermal veins and sedimentary deposits. Sphalerite typically crystallizes in the cubic crystal system, forming various crystal habits such as tetrahedral, dodecahedral, or cubic shapes.

The chemical formula \(ZnS\) indicates that each unit of sphalerite contains one zinc \((Zn)\) atom bonded to one sulfur \((S)\) atom. The mineral is typically yellow, brown, or black in color, but it can also occur in transparent or translucent crystals. Sphalerite is often associated with other sulfide minerals, such as galena \((PbS)\), pyrite \((FeS_2)\), and chalcopyrite \((CuFeS_2)\).

As an ore of zinc, sphalerite is an important source of this metal for industrial and commercial applications. Zinc is primarily used in the production of alloys, such as brass and bronze, as well as in galvanizing steel to protect against corrosion. Sphalerite is also valued by collectors for its distinctive crystal forms and attractive colors.