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Bureau of Mines / Minerals yearbook: Metals and minerals 1978-79
Year 1978-79, Volume 1 (1978-1979)

Zlobik, Alvin B.
Mica,   pp. 601-613 ff. PDF (1.1 MB)


Page 601

  601Mica 
By Alvin B. Zlobik1 
 Sheet mica production was limited to a small quantity of handpicked, low-quality
muscovite from North Carolina. Domestic scrap and flake mica production in
1978 increased 8% over that in 1977 while production in 1979 decreased 4%
from that in 1978. Sales of ground mica during the 1978- 
79 period remained near the 1977 level of 
122,000 tons.2 
 Fabrication of mica block decreased 46% in 1978 but increased 16% in 1979.
Fabrication of mica film decreased 11% and 38% in 1978 and 1979, respectively.
Consumption of mica splittings increased 34% to 5.5 million pounds in 1978
but decreased 12% to 4.9 million pounds in 1979. 
 Exports of all forms of unmanufactured 
mica decreased 10% to 9,200 tons in 1978, 
but increased 26% to 11,600 tons in 1979. 
Imports of all forms of mica increased 86% 
to 7,200 tons in 1978 and increased again to 
10,300 tons in 1979. 
 Legislation and Government Programs.—The total government stockpile
inventory of natural sheet mica was reduced to 30.1 million pounds by December
31, 1979. Sales of sheet mica by the General Service Administration (GSA)
during 197879 totaled 1,688,000 pounds; this included 
1,139,000 pounds of muscovite splittings and 
549,000 pounds of phlogopite splittings. There were no sales of block or
film mica in 1978 or 1979. 
Table 1.—Salient mica statistics 
1975 
1976 
1977 
1978 
1979 
United States: 
Production (sold or used by producing companies): 
 Sheetmica thousand pound&_  Value thousands_ Scrap and flake mica2
thousand
short tons_ —  Value2 thousands.. Ground mica2 thousand short tons..
— 
5 
$3 
132 
$5,205 
112 
5 
$3 
123 
$5,667 
115 
1 
(1) 
129 
$7,039 
122 
(1) 
(1) 
139 
$7,916 
124 
1 
(1) 
134 
$7,708 
122 
 Value2 thousand&. — 
Consumption: 
 Block thousand poUnds... — 
 Value thousands_ 
 Film thousand pounds~. 
 Value thousands.. 
 Splittings thousand pounds... — 
 Value thousands. 
 Exports thousand short tons...... 
 Imports do.~ 
World production thousand pounds... — 
$9,366 
616 
$1,581 
7 
$27 
4,746 
$2,634 
6 
8 
r447371 
$10,207 
524 
$1,369 
10 
$44 
5,025 
$3,226 
8 
5 
r465 231 
$11,906 
439 
$952 
9 
$38 
4,144 
$2,718 
10 
4 
r490134 
$12,979 
239 
$1,328 
8 
$34 
5,537 
$3,031 
9 
7 
534,058 
$14,522 
277 
$1,841 
5 
$25 
4,877 
$3,248 
12 
10 
527,773 
r~ 
' Less than 1/2 unit. 
2Data have been revised to exclude low-quality sericite. 


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