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Geologic map of the baritic carbonate body near Mountain Pass, San Bernardino County, California

January 1, 1951

A geologic map of an important deposit of rare earth metals studied recently by Geological Survey geologists near Mountain Pass, California has been completed Secretary of the Interior Oscar L. Chapman announced today. The discovery of this deposit was announced on January 16, and because of the great interest that has been shown in the deposit, the map is being made available for public inspection immediately, Secretary Chapman explained.

The deposit covered by this map is in San Bernardino County, California near where prospectors made the original discovery on the Birthday claims in 1949. Subsequent studies by the Geological Survey have shown that an area roughly 6 miles long and 2 miles wide, extending southeast from the original discovery, contains a number of other rare carth-bearing deposits, including the large ore body covered by this map.

This ore body is made up largely of a carbonate mineral and barite, but contains significant quantities of the rare earth mineral, bastnasite as well. It is exposed over an area 2,400 feet long and 400 feet wide.

Publication Year 1951
Title Geologic map of the baritic carbonate body near Mountain Pass, San Bernardino County, California
DOI 10.3133/ofr5138
Authors William N. Sharp, Jerry Chipman Olson
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 51-38
Index ID ofr5138
Record Source USGS Publications Warehouse
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