When studying the color of rutile, a project sponsored by the Geophysics Branch of the O.N.R., W. A. Weyl and T. Forland∗ discovered that the blue-grey color which is characteristic for partly reduced rutile may be obtained in an oxidizing atmosphere if an occasional Ti4+ ion is replaced by a cation of a valency higher than four (Sb5+, Cb5+, W6+).