Nodular, orbicular, and banded chromite in northern California

IN I930 Mr. A. F. Duggleby gave me a specimen of orbicular chromite from the Octopus claim, in Siskiyou County, Calif., showing two generations of chromite, one older than the associated olivine and one younger. In November, I93I, I examined briefly a number of deposits in northern California, in search for chromite showing similar and related textures. Some of the more unusual and genetically significant occurrences are described in this paper.

Most of the chromite localities here described are in Siskiyou County, northern California. Localities I and 2 are in the Seiad Quadrangle, where a belt of chromite-bearing dunite, striking northwest, extends from McGuffy Creek, near Scott Bar, into Oregon. Other deposits are in southern Siskiyou, Shasta, and Trinity Counties.