Ulvospinel

Ulvospinel

 

a mineral of the subclass of multiple oxides, Fe2Ti04. Ulvospinel crystallizes in the isometric system, and its structure is the inverted form of the spinel structure. It forms solid solutions with magnetite. Lattice disintegration structures form upon cooling. Ulvospinel is found in the form of irregularly shaped black grains and phenocrysts. The unit cell parameter a0(8.40-8.53 Á), the Curie point (from 580° to - 150°C), and the density (5,200-4,800 kg/m3) vary in a regular manner in the magnetite-ulvospinel series. Upon oxidation, ulvospinel alters to ilmenite. It is found in ultrabasic magmatic rocks and lunar basalts. Ulvospinel is a component of complex titanium-magnetite ores.

References in periodicals archive ?
In metamorphic rocks, the ulvospinel component is usually totally exsolved, and titaniferous magnetite is oxidized to an admixture of Ti-low magnetite and ilmenite.
with negligible amounts of the ulvospinel component (0.
The composition of larger lobate grains shows their pertinence to titaniferous magnetite with a higher content of ulvospinel molecule ([Fe.
Okorusu magnetites exhibit abundant exsolutions of ulvospinel in a characteristic cloth texture, and oxidation exsolution occurred subsequently.