Rocky Ridge mine

Mica Mine in Mitchell county, North Carolina

Rocky Ridge mine

Principal periods worked WWII
Workings Cut 18, adit 15
Description of muscovite Green, mineral inclusions, bent, cracked
Production Small sheet
Shape Lens
Size 0.5-3T
Strike NW
Dip SW
Relation to wallrock Concordant
Wallrock Biotite gneiss
Extent of weathering Weathered
Remarks Pl-Q-M pegmatite, fine to medium grained; accessory garnet, sericite.
Source of information USGS

Geographic context


Principal periods worked
WWI World War I
WWII World War II
int intermittent
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