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- Mica deposits of the Blue Ridge in North Carolina
Mica Mine in Avery county, North Carolina
Fall Branch mine
Principal periods worked |
Pre-WWII |
Workings |
Caved |
Description of muscovite |
Light green, small, bent, ruled |
Production |
Moderate scrap |
Size |
Largest 10 T |
Strike |
NE |
Dip |
NW |
Relation to wallrock |
Concordant |
Wallrock |
Interlayered hornblende and biotite gneiss |
Remarks |
Pl-Q-P-M pegmatite, fine grained; accessory garnet, epidote. |
Source of information |
USGS |
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 |