Sign up for Lesson Plans, discounts & more!
The sulfates are made up of one or more metals in combination with sulfur and oxygen. The sulfur and oxygen atoms form a unit with one sulfur atom in the center and four oxygen atoms forming a square around it. These atoms form a tetrahedron crystal pattern. The chemical formula of the group is:SO4
This class of minerals tends to be evaporates or forms from volcanically heated water. As a group they are soft and pale in color and sometimes transparent or translucent.
There are many minerals in the sulfate group but most are rare in occurrence. Anhydrate, barite, and gypsum are minerals that are common in this class.
Barite is a sulfate mineral with a chemical formula of BaSO4, sometimes called heavy spar. Its chemical name is barium sulfate.
Selenite is a very common chemical sedimentary mineral. Its chemical formula is Calcium Sulfate dihydrate CaSO42H20. It is a form of gypsum.
Celestite is made up of strontium sulfate. The chemical formula is SrSO4. Its name comes from Latin, caelestis meaning celestial.