pseudobrookite

from The Century Dictionary.

• noun A mineral occurring in minute rectangular tables in cavities in some volcanic rocks, as andesite. It resembles brookite, and is related to it in composition, consisting of the oxids of titanium and iron.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun mineralogy An orthorhombic-dipyramidal mineral containing iron, magnesium, oxygen, and titanium.