Slippery Elm mine

Mica Mine in Avery county, North Carolina

Slippery Elm mine

Principal periods worked WWII, 1953-60
Workings 3, adits, stopes, drifts in area 300 by 450.
Description of muscovite Green, clear, moderately bent, ruled, tied.
Production Large sheet, feldspar.
Shape Irregular, branching, pinch and swell.
Size 1-10 T
Strike Variable
Dip Variable
Plunge Variable
Relation to wallrock Discordant
Wallrock Interlayered hornblende and biotite gneiss, biotite alteration
Extent of weathering Unweathered
Remarks Pl-Q-M walls zone, medium to coarse grained; P-Q core, coarse grained, discontinuous; accessory garnet, allanite, pyrite, thulite. Cut by numerous joints and faults and a diabase dike.
Source of information USGS, CMC, OF.

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