Page 1201

  1201Thorium 
By Roman V. Sondermayer' 
As in the past, there was no direct mine 
production for thorium as such during 1972, and demand for thorium was not
the decisive factor in determining its supply. Production of thorium was
essentially a byproduct of the monazite operations for rare earths. Consequently,
there was a continuing and excessive stock of thorium- 
bearing raw materials. The weak market continued, but the long-term potential
for use of thorium was considered good. 
Demand for thorium hardener, used in magnesium alloys for aerospace applications,
increased slightly. New orders for thorium-uranium-fueled high-temperature,
gas-cooled reactors (HTGR) improved the long-range demand potential for thorium
nuclear fuels. Continuing research may introduce new industrial applications
for thorium and its compounds in metallurgy and nuclear fuels, thus resulting
in larger consumption of thorium. 
The most significant events related to 
thorium during 1972 were the beginning of a new beach-sand (containing monazite)
operation in Florida, the preliminary accord for the sale of two HTGR's to
Southern California Edison Co., and the participation of Gulf General Atomic
Co. (GGA) in construction of a HTGR in West Ger. 
many. 
 Legislation and Government Programs. 
—The entire inventory of thorium held by the Government was authorized
for disposal. However, there was no response to the request for bids during
1972, and thorium and its compounds were not sold from the stockpile. At
the end of 1972, 1,789 tons of thorium-oxide (Th02) equivalent were held
by the Government in stockpile. 
 Effective January 1, 1972, under the "Kennedy round" schedule of tariff
reductions, ad valorem duties were reduced to 17.5% on thorium compounds,
6% on metal, and 7.5% on thorium alloys. 
DOMESTIC PRODUCTiON 
 Mine Production.—Production of byproduct monazite from a Pleistocene
beachsand deposit, located 35 miles inland and 10 miles fron Green Cove Springs,
Fla., started in October 1972. Titanium Enterprises, jointly owned by American
Cyanamid Co. and Union Camp Corp., became the second domestic monazite producer.
In addition to monazite, mine products included ilmenite, leucoxene, rutile,
and zircon. 
 Humphreys Mining Co., with its operation near Folkston, Ga., remained the
largest producer of monazite in the country. Output was slightly lower in
1972. Estimated Th02 content remained at 5%. Heavy-mineral sands were mined
by suction dredge for their titanium minerals and zircon content. The byproduct
mona- 
zite was sold under contract to W R. Grace & Co., Chattanooga, Tenn.
Monante was processed essentially for its rare earths oxide (REO) content.
Thorium-bearing residues were stockpiled for processing as needed. 
 Humphreys Mining Co. continued land rehabilitation of an area disturbed
by mining. Mill waste was used as fill, and, after grading, topsoil was respread,
fertilized, and planted with grass. The company was presented with the State
of Georgia first honor award for land reclamation achievements. 
 Refinery Production.—The principal domestic firms processing monazite
for 
 1 Physical scientist, Division of Nonferrous Metals.