kalkowskite

kalkowskite

[kal′kȯf‚sīt]
(mineralogy)
Fe2Ti3O9 A rare, brownish or black mineral composed of an oxide of iron and titanium, usually with small amounts of rare-earth elements, niobium, and tantalum.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.