Middle Ridge mine

Mica Mine in Mitchell county, North Carolina

Middle Ridge mine

Principal periods worked WWII
Workings Adit 85(?), shaft 18
Description of muscovite Brown, minor "A" structure, mineral inclusions, cracked, ruled.
Wallrock Mica gneiss
Extent of weathering Weathered
Remarks Kaolinized F-Q-M pegmatite, poorly exposed.
Source of information USGS

Geographic context

Abbreviations

Principal periods worked
WWI World War I
WWII World War II
int intermittent
Production
Small < 500 lb
Moderate 500-10,000 lb
Large > 10,000 lb
Size of pegmatite
D depth
L length
T thickness
avg average
Internal structure
B biotite
F feldspar
M muscovite
P perthite
Pl plagioclase
Q quartz
Source information
CMC Colonial Mica Corporation
DMEA Defense Minerals Exploration Administration
OME Office of Minerals Exploration
USGS U.S. Geological Survey
OF USGS open-file reports and maps