Sacramento porphyry. Main phenocrysts are altered andesine-oligoclase; also present are hornblende and biotite. Lake County, Colorado. 1935.
Dates
Date Taken
1935
Summary
Sacramento porphyry. Main phenocrysts are altered andesine-oligoclase; also present are hornblende and biotite. X 40; plain transmitted light. Board of Trade Amphitheater. Lake County, Colorado. 1935. Figure 44, in U.S.Geological Survey Professional paper 235. 1953.
Summary
Sacramento porphyry. Main phenocrysts are altered andesine-oligoclase; also present are hornblende and biotite. X 40; plain transmitted light. Board of Trade Amphitheater. Lake County, Colorado. 1935. Figure 44, in U.S.Geological Survey Professional paper 235. 1953.
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