1406 MINERALS YEARBOOK, 1941

tons ~f crude fiuorspar (calculated to be equivalent to 25,000 tons of finished
fluorspar) and 31,997 tons of finished fluorspar.

Stocks of fluorspar at mines or shippihg points in the United States, December
31,
1940 and 1941, by States, in short tons
State
1940
 ----—-— ———

Crude 1 Finished Total


1941

— Crude' Finished Total


Arizona                                                 
California                        
Colorado                        
flhinois                          
Kentucky -                       
New Mexico -Texas                                   Utah                
          Washington                       
150
205
23,934
3,906
2,604
60
---
364
18,269
22,707
2,483
43
 
150
569
42,203
26,613
5,087
43
60
 
30
150
666
23,711
12, 579
2,539
 
525
434
19,966
10,981
425
43
110
38
30
150
1,100
43,677
23,560
2,964
43
(335
38

30,859
43,866
74,725
40,200
31,997
72,197
' The greater part of this ~rude (run~of-mine) fluorspar must be beneficiated
before it can be marketed.

TECKNOLOGIC DEVELOPMENTS

 The capacity of flotation plants in the United States was increased substantially
in 1941 by additions to or improvements in present mills; new plants are
now under construction. At the plant of the Rosiclare Lead & Fluorspar
Mining Co., ' more flotation cells were added, the ball mill was enlarged,
and other improvements were made. The Mahoning Mining Co. and Aluminum Ore
Co. expanded and improved their flotation mills during 1941. The Colorado
Fluorspar Corporation made improvements in its mill at Salida, Cob.; P. L.
Grattan is rebuilding his flotation plant at Doming, N. Mex.; and J. Irving
Crowell, Jr., installed flotation cells in his mill near Beatty, Nev. The
General Chemical Co., which operates a flotation plant at Deming, N. Mex.,
is constructing a flotation plant near Jamestown, Cob., to treat ore from
its mines in Boulder County. The Fluorspar Processing Co. is installing a
combination flotation-concentrating mill near Salida, Cob. Output of flotation
concentrates was 64,627 short tons in 1941 comparedwith 41,467 tons in 1940.
 A Bendelari jig, the first to be used in the Illinois-Kentucky district,
was installed in the mifi of the Fluorspar Products Corporation near Rosiclare,
Ill. This type of jig is also used by Navajo Fluorspar Mines in its mill
near Grants, N. Mex.
 Air tables, an innovation in milling fluorspar, were included in the equipment
installed in the mill of the Big Creek Fluorspar Co. near Rosiclare, Ill.
 A method of concentrating fluorspar ores is covered by United States Patent
2,263,552 granted to C. 0. Anderson and others, assignors to Mahoning Mining
Co. A principal object of the invention is to provide a method for flotation
concentration of fluorspar from ores high in calcite, by means of which acid-grade
fluorspar can be produced commerciairy without desliming treatment before
flotation of the ore. A further object of the invention is to provide a method
of this character that will avoid loss of material ore values through removal
of the fines or slimes preparatory to flotation. Another object is to provide
a method of flotation concentration of fluorspar