n. , (mineralogy) A variety of hematite that is pseudomorphic after magnetite crystals.
the GNU version of the Collaborative International Dictionary of English
n. Iron sesquioxide in isometric form, probably a pseudomorph after magnetite.
The Century Dictionary and Cyclopedia
n. Iron sesquioxid in isometric crystals, probably pseudomorph after magnetite. It occurs occasionally on a large scale, as in the Lake Superior iron region and the Cerro de Mercado in Mexico.
Word Usage
"Various analyses of this "martite" ore show from forty-four to sixty-eight per cent. of iron, and very low in both sulphur and phosphorus."