570 MINERALS YEARBOOK, 1967 
 
County. Mica was to be shipped to the plant from various locations in northern
New Mexico. 
 
 Perlite.—Output of perlite was unchanged, as production continued
at four operations. In Taos County output by Grefco, Inc., Johns-Manviile
Perlite Corp., and United Perlite Corp. was shipped to out-of-State expanding
plants. In Valencia County, United States Gypsum Co. mined perlite from a
quarry northeast of Grants, which was milled locally. The material was used
at other company plants. 
 Perliite is used principally as buildingplaster aggregate, filter aids,
and concrete aggregate. New Mexico continued to be the major source of perlite.

 
 Potash.—Although production of potassium salts (potash) declined slightly,
value of production declined $1 7.5 million or 16 percent to $91.1 million.
A sharp drop in prices, amounting to about $5.00 per ton of K20 equivalent,
was mainly responsible for the decline in production value. The closing of
one operatio~ and the curtailment of production at another also affected
output and value. The production declines in the Carlsbad potash basin were
related to the start of operations at four mines in the newly discovered
potash fields in Saskatchewan, Canada. Reportedly, output from these mines
was about the same as from the seven Carlsbad producers. Six more mines were
under construction in Canada. 
 
 
Table 12.—Crude perlite sold or used by 
producers 
 
 
 
Value 
Year 
Short tons 
(thousands) 
1963                 
259,113 
$2,212 
1964                
286,329 
2,568 
1965                
331,011 
2,905 
1966                
1967                 
343,334 
346,586 
3,423 
3,424 
 United States Borax & Chemical Corp. (U.S. Borax) closed its Carlsbad
operation in November, 10 months earlier than had been originally scheduled.
By yearend 755 of the 850-man work force had been laid off. Progress in construction
at the potash operations of the company in Canada and accumulated inventories
contributed to the hastened closing. Beginning production 
in 1931 under the name U.S. Potash, the company was the first to operate
in the Carlsbad potash basin. Although substantial ore reserves were reported,
the grade of the ore was too low to sustain operations. Options to purchase
the properties were not exercised. London-based Borax Holdings owned 73 percent
of U.S. Borax. 
 International Minerals & Chemical Corp. (IMC) reduced its potash-operations
work force by about 50 percent in July. Declining ore grade, lower potash
prices, and higher production costs caused the layoff of 385 employees. The
company announced that a new metallurgical process would make possible the
treatment of mixed sylvite-langbeinite ores previously considered unamenabie
to treatment. Sylvite is a potassium chloride mineral; langbeinite is a potassium
sulfate. Processing of the mixed ore reportedly would involve heavy-media
separation of the two minerals. Installation of the new process, at a cost
of about $2 million, was to be completed in about 1 year. Although output
would not increase, better economies would result. Langbeinite, increasingly
in demand, is not present in commercial quantities in the Canadian potash
beds. The only other domestic production has been by Duval Corp. at that
company's Carlsbad operations. 
 Duval Corp. temporarily closed the Wills Weaver potash mine, the northernmost
mine in the potash basin. The company continued to operate the new Nash Draw
mine, the southernmost in the basin, and the Saunders mine located at the
refinery near the center of the basin. Because of the wide geographical distribution
of the properties, the company decided that a more economic operation could
be obtained by closing the one mine and increasing output at the others.
The affected employees were offered employment at company operations in Arizona.
Sylvite ore was produced at the Saunders mine, and langbein'ite at the Nash
Draw mine. The Nash Draw also contained sylvite at a higher level in the
mine where future production was planned. The company continued research
on a new potash refining process; construction began on a sulfate granulation
plant. 
 Potash Corporation of America (PCA) Division, Ideal Basic Industries, Inc.,
completed expansion of the refining section where chemical-grade muriate
was pro-