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PRICES 
35 mesh                      
48 mesh                      
100 mesh                  
200 mesh                      
325 mesh                      
Per short tons 
$58 
62 
65 
73 
Nominal 
690 MINERALS YEARBOOK, 1972 
DOMESTIC PRODUCTION 
 Kyanite was produced in the United States in 1972 from three open pit mines,
two in Virginia and one in Georgia. In addition to the hard-rock production,
a minor quantity of kyanite-sillimanite concentrate was recovered in the
process of extracting titanium and zirconium minerals from a beach sand deposit
in Florida. Kyanite Mining Corp. operated the Willis Mountain mine in Buckingham
County, Va., and the Baker Mountain mine in adjoining Prince Edward County,
Va. C-E Minerals, Inc., operated the Graves Mountain mine in Lincoln County,
Ga. E. I. du Pont de Nemours & Co., Inc., operated the Trail Ridge mine
and mill in Clay County, Fla. 
 Domestic kyanite output in 1972, as measured by the quantity sold or used,
was fractionally lower in both tonnage and total value than in 1971. Specific
kyanite production statistics for 1972 (as well as for all previous years
since 1949) are withheld because the predominant position of the two major
producers would make publication of even national totals a disclosure of
each firm's confidential data. 
 Synthetic mullite, produced in 1972 by eight companies at operations in
seven States, amounted to 16% less in tonnage than in 1971 and 18% less in
total value. The 1972 output consisted predominantly of high-temperature
sintered material, the average unit value of which was substantially below
that reported for fused material. Leading in tons produced were Babcock &
Wilcox Co., Richmond County, Ga.; Mullite Corp. of America, Sumter County,
Ga.; H. K. Porter, Inc., Fairfield County, Conn.; and Charles Taylor &
Sons, Inc., Greenup County, Ky.; whose combined outputs amounted to 86% of
the 1972 national total. 
Table 1.—Synthetic mullite production 
in the United States 
(Short tons and thousand dollars) 
Year 
Quantity 
Value 
1968                   
1969                  
1970                  
1971                   
1972                   
36,014 
48,588 
55,516 
55,077 
46,389 
5,758 
6,847 
8,840 
4,945 
4,080 
CONSUMPTION AND USES 
 Kyanite and related minerals, conforming to the established end-use pattern,
were consumed in 1972 mostly in the manufacture of high-alumina or mullite
class refractories and in lesser quantities as ingredients in some ceramic
compositions. Imported Indian kyanite was calcined in its natural lump form,
after which it was usually separated into designated particlesize ranges
for use chiefly as a grog. Domestic kyanite already ground to minus 35 mesh,
as required by the flotation process used in separating it from the accompanying
quartz gangue, was marketed in the raw form or after heat treatment, as mulEngineering
and Mining Journal, December 1972, listed the following prices per short
ton (unchanged from December 1971 quotations) for kyanite, f.o.b. Georgia,
in bags (bulk shipments $2.00 less per ton): 
lite, which was sometimes further reduced in particle size. In the 35- to
48-mesh range, the mineral was employed mostly in refractories applications
such as for hightemperature mortars or cements, ramming mixes, and castable
refractories, or with clays and other ingredients in refractory compositions
for the making of kiln furniture, insulating brick, firebrick, and other
refractory articles of a wide variety of types. More finely ground material,
minus 200 mesh for example, was used especially in body mixes for sanitary
porcelains, wall tile, precision casting molds, and miscellaneous special-purpose
ceramics.