Penstock mine

Mica Mine in Avery county, North Carolina, this site also known as Race?

Penstock (Race?) mine

Principal periods worked WWI, WWII
Workings Cut 100, adits
Description of muscovite Green, tied, stained, bent, ruled
Production Small sheet, feldspar.
Shape Lenses
Size 20 T
Strike NW
Dip SW
Relation to wallrock Concordant(?)
Wallrock Mica gneiss
Extent of weathering Unweathered
Remarks P-Pl-Q-M pegmatite, coarse grained accessory allanite.
Source of information USGS, CMC

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