CaFe2Si2O6

CaFe2Si2O6 is the chemical formula for a mineral belonging to the pyroxene group. Specifically, it is a calcium-iron pyroxene. Pyroxenes are a group of inosilicate minerals that form an important series in igneous and metamorphic rocks. They share a common crystal structure characterized by single chains of silica tetrahedra.

In CaFe2Si2O6, calcium (Ca) occupies the M2 cation site, and iron (Fe) occupies the M1 cation site within the pyroxene structure. The silicon (Si) and oxygen (O) form the characteristic tetrahedral chains. This particular composition is often referred to as ferrosalite, a variety of the clinopyroxene salite (CaMgSi2O6) where magnesium is completely or partially substituted by iron.

The physical properties of CaFe2Si2O6 are typical of pyroxenes. It usually appears as prismatic crystals and can exhibit various colors, often shades of green or brown, due to the presence of iron. Its hardness is around 5-6 on the Mohs scale, and it has a density typically between 3.4 and 3.6 g/cm³.

CaFe2Si2O6 is found in various geological settings. It is commonly encountered in mafic and ultramafic igneous rocks, such as basalts and gabbros, and can also occur in some metamorphic rocks. Its presence can provide clues about the temperature, pressure, and chemical conditions under which these rocks formed.