Joe Davis Rock mine

Mica Mine in Avery county, North Carolina, this site also known as Big Andy

Joe Davis Rock (Big Andy) mine

Principal periods worked WWII, 1956
Workings Cut 250, adit 160, stope
Description of muscovite Ruby to brownish green, cracked, bent, minor stain, small.
Production Small sheet
Shape Lenses
Size 0-20 T
Strike N
Dip E
Relation to wallrock Concordant
Wallrock Biotite gneiss
Extent of weathering Unweathered
Remarks Pl-P-Q-M pegmatite, medium to coarse grained; accessory biotite.
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