Diabase, Lost Creek, Granite County, Montana. Circa 1907.
Dates
Date Taken
1907
Summary
Diabase. Lost Creek sill. Shows intergrowth of quartz with hornblende and with plagioclase. The plagioclase in the intergrowth has the same orientation as the adjacent large crystal. The quartz areas marked "Q" have all the same orientation. Those marked "Q2" have another uniform orientation. Crossed nichols. SP. 8 C 67. x 60. Granite County, Montana. Circa 1907. Published in U.S. Geological Survey Professional Paper 78, Plate XII-A. 1913.
Summary
Diabase. Lost Creek sill. Shows intergrowth of quartz with hornblende and with plagioclase. The plagioclase in the intergrowth has the same orientation as the adjacent large crystal. The quartz areas marked "Q" have all the same orientation. Those marked "Q2" have another uniform orientation. Crossed nichols.
SP. 8 C 67. x 60.
Granite County, Montana. Circa 1907.
Published in U.S. Geological Survey Professional Paper 78, Plate XII-A. 1913.
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