The Probert Encyclopaedia of Rocks & Minerals

HEMATITE

It is the most abundant and important ore or iron. Has been found in enormous deposits in the United States and elsewhere. Many samples are soft as the hematite is sedimentary or weathered iron oxide and the true hardness is not being measured. Hematite has the formulae Fe2O3 and a relative hardness of 7.
Research Hematite