Minerals identify

Know how to recognize them

Jacobsite

Oxide mineral,spinel group,spinel structural group

Jacobsite is a manganese oxide mineral group and forms a solid solution. The chemical formula is MnFe2O4 or with oxidation states and substitutions: (Mn2+,Fe2+,Mg)(Fe3+,Mn3+)2O4.

It occurs as a primary phase or as alteration of other manganese minerals during metamorphism Typical associated minerals include hausmannite, pyrolusite and magnetite. It is a ferrimagnetic substance, which is weakly attracted by a magnet.

It was first described in 1869 and named for the Jakobsberg Mine, Nordmark, Sweden

Identification

Color of mineral

Brown
Black

Mohs scale ( mineral hardness )

5.5

The streak

Red
Brown
Black

Luster ( interacts light )

Metallic

Crystal ( diaphaneity )

Isometric