Principal periods worked | Pre-WWII |
---|---|
Workings | Cut 35 |
Description of muscovite | Light brown, hard, moderate stain, mineral inclusions. Light green, "A" structure, tied, cracked, ruled. |
Production | Small sheet |
Shape | Tabular (?) |
Size | >20 T |
Strike | NE |
Dip | SE |
Relation to wallrock | Concordant |
Wallrock | Mica gneiss |
Extent of weathering | Unweathered |
Remarks | Pl-Q-M pegmatite, fine to medium grained; accessory sericite, garnet, biotite. |
Source of information | USGS |
WWI | World War I |
WWII | World War II |
int | intermittent |
Small | < 500 lb |
Moderate | 500-10,000 lb |
Large | > 10,000 lb |
D | depth |
L | length |
T | thickness |
avg | average |
B | biotite |
F | feldspar |
M | muscovite |
P | perthite |
Pl | plagioclase |
Q | quartz |
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 |