The Emma Bell Deposit, Siskiyou Co., California : a possible low-grade source of chromite

Open-File Report 83-816
By: , and 

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Abstract

The Emma Bell chromite deposit in Siskiyou County, California contains over 5 million tons of dunite averaging about 4 percent Cr2O3. Chromite is not evenly disseminated throughout the dunite, however. For the most part the deposit consists of many chromite-rich bands in sharp contact with, and separated by, common dunite containing 1 to 2 percent accessory chromite. Electron microprobe and petrographic analysis of accessory chromite shows that it is fine grained (average grain size 0.14 mm), generally lower in Cr2O3, and has a lower Cr/Fe ratio than segregated chromite. In addition, unusual patchy zoning is exhibited by some accessory chromite. These patchy zones are extremely rich in iron (>60 percent total iron oxide). The negative factors such as the fine-grained nature of the accessory chromite and high iron content compared to segregated chromite, could be overcome by the very large tonnage in the deposit.

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title The Emma Bell Deposit, Siskiyou Co., California : a possible low-grade source of chromite
Series title Open-File Report
Series number 83-816
DOI 10.3133/ofr83816
Edition -
Year Published 1983
Language ENGLISH
Publisher U.S. Geological Survey,
Contributing office(s) Eastern Mineral and Environmental Resources Science Center
Description i, 16 p. :ill ;28 cm.