Patent No. U.S. 6,579,356 B2
Engelhard Corp. has been granted a patent for a brown pigment composition, comprising approximately 30%-80% by weight of iron oxide; five to 50% by weight of chromium oxide; and 2.5%-50% by weight of alumina and silica components. The alumina and silica comprising from about 40% to about 70% by weight of at least one alumina component and approximately 30%-60% by weight of at least one silica component. The brown pigment composition exhibits excellent resistance to weathering.