MOLYBDENUM AND VANADIUM 631

 This plant was designed to mill 10,000 tons per day, but it was not long
before 12,500 tons was being treated during periods of peak demands. During
the summer of 1941, to meet defense needs, the mill has been required to
treat 15,500 tons per day. This has been accomplished with little plant expansion
and at no loss in recovery. To increase capacity still further, one more
primary section is being built. This will bring capacity to 18,000 tons per
day, which can be stretched to 20,000 tons at a small sacrifice in recovery.

 The foregoing article also describes milling methods in considerable detail;
additional information on mining methods, with special reference to blasting
practice, was made available by Barker.6
 New Mexico.—The Molybdenum Corporation of America continued to operate
its mine and mill near Questa, Taos County. Ore of relatively high grade
is mined, and the tonnage treated is comparatively small. The Nevada Consolidated
Copper Corporation recovered molybdenite as a byproduct from its copper concentrate
at the Chino property in Grant County.
 Utah.—The only producer in Utah in 1941 was the Utah Copper Co. at
Bingham. The molybdenite concentrate is obtained as a byproduct in the concentration
of copper ores and in the re-treatment of molybdenum-bearing concentrates.

EXPORTS AND IMPORTS

 Total exports of molybdenum ore and concentrates in 1941 were 15,345,251
pounds, containing 7,640,330 pounds of molybdenum, with a value of $5.379,367;
this total represents a 16-percent increase over 1940 in molybdenum contained.
Large increases were shown in shipments in 1941 to Canada, U. S. S. R., and
United Kingdom. Exports of molybdenum to France, Italy, and Japan ceased.
Chile entered the list of countries receiving molybdenum from the United
States, whereas no exports to Brazil were recorded during 1941.

Molybdenum ore and concentrates azported from the United States, 1940—41,
by
countries
Country
1940


1941



Gross
weight
(pounds)
Molybde-
nuin content
(pounds)
Value
Gross
weight
(pounds)
Molybde.
num content
(pounds)
value
Brazil                  
Canada.                
Chile
France                 
Italy                   
Japan                  
TJ. S. S. R               
United Kingdom         
Other countries           
332,676
554,951
                                  
5, 299,380
1,650,650
133,215
654, 789
3,985,961
66, 172
201, 362
284, 458
2, 740, 065
849, 578
117, 100
336, 289
2,019,801
36,061
$149, 856
255,256
2,021,685 ~31, 696
 5.3,929
241,113
1,514,852
 35,613
974,321
 30,255



4,715,284
9,625,391
500,402
15,000


2, 367, 492
4, 757,436
 
$400, 706
 12,000



1,777,185
3,189,476

12, 677, 794
6, 584, 714
4,904,000
15,345,251
7,640,330
5,379,367
 Imports of molybdenum in molybdenum ore and concentrates in 1941 totaled
4,300 pounds; there were none in 1940. In 1939, 26,347 pounds were imported
in ferromolybdenum, etc.
' Barker, Claude L., The World's Largest Molybdenum Mine: Mines Mag., vol.
31, No. ii, November 1941, pp. 558-564, 568.

4!T779—4:l-—-~ 42