COLUMBIUM AND TANTALUM 315 
 
 Rwanda.—Late in the year, the Société Minière
du Rwanda (SOMIRWA) reportedly had gone into receivership after declaring
a cessation of payments backdated to July. A heavy debt burden, low prices,
and currency difficulties were cited as reasons for SOMIRWA's problem. SOMIRWA,
owned 49% by the Rwandan Government and 51% by the Belgian Compagnie Geologique
et Minière des Ingenieurs. et Industriels Belges, has produced
about
60 tons of tantalite ore annually. 
 Thailand.—Columbite-tantalite production continued to decline
and
was over 40% 
lower than in 1984; there was no reported 
production of struverite, compared with 33 
tons produced in 1984. 
 By midyear, Billiton Thailand Ltd. had closed its offshore tin dredging
operation. Billiton indicated that cutbacks in production under the ITC's
export quota for Thailand and declining ore reserves had made the operation
unprofitable. However, the closure of the offshore operation was not expected
to affect production at Billiton's tin smelter, Thailand Smelting and Refining
Co. Ltd. (Thaisarco) in Phuket, which secures its tin concentrates from all
Thai tin miners. By yearend, proposals by former employees of the company
to buy Billiton's facilities and resume offshore dredging activities had
been turned down by Thai authorities. 
 At yearend, Thailand's Mineral Resources Department and ThaisarcO were taking
steps to establish a tin market in Phuket. Prior to suspension of trading
on tin markets in late October, Thaisarco was required to buy local tin concentrates
on the basis of the Malaysian KLTM price but sold most of its tin output
on the basis of the lower LME price. 
 In midyear, Thaisarco announced an agreement to supply most of its high-grade
tantalum-bearing tin slags to the Thailand Tantalum Industry Corp. Ltd. (TTIC)
for use 
at TTIC's columbium and tantalum extraction facility in Phuket. Shipments
reportedly were to begin in July. Thaisarco, with a tin metal capacity of
about 42,000 tons annually, formerly exported all of its tin slag production,
and two U.S. firms, Cabot and Fansteel, were major recipients. 
 The TTIC completed construction of the chemical plant phase of its columbium
and tantalum extraction facility, with commercial production planned by yearend
1986. Reports indicate that the plant will have an initial annual capacity
to produce in excess of 300 tons each of Cb20, and Ta,O,, and over 500 tons
of potassium tantalum fluoride. 
 The Thai Pioneer Enterprise Co. Ltd. (TPE) reportedly was seeking $5.5 million
in financing to reopen its tin smelter, which had been closed since midyear
1982. The smelter, with an annual tin metal capacity of about 4,000 tons,
also had produced tantalum-bearing tin slags. Also, the Thai Government reportedly
granted TPE an exemption from the 4.4% tax normally applied to tin metal
exports. 
 Early in the year, the Thai Ministry of Science, Technology and Energy reportedly
signed a $1.78 million technology transfer agreement with Japan's Metal Mining
Agency. Under the terms of the agreement, Japan will provide the expertise
needed to develop a technique to separate and extract columbium, tantalum,
and other rare metals contained in waste derived from milling tin ores in
Thailand. 
 Zaire.—Commercial-scale production of pyrochlore from the Lueshe
carbonatite
deposit reportedly was planned by yearend 1986. Production had been delayed
awaiting decision on the choice of power for the new operation. A 1984 study
had suggested two power alternatives, a linkup with the existing Bukavu-Goma
powerline or the construction of a new powerplant at Kwindi. 
 
TECHNOLOGY 
 
 The Bureau of Mines working with the Defense Reutilization and Marketing
Service (DRMS) developed identification and separation techniques for recovery
of tantalum from electronic scrap. The joint effort enabled DRMS to sell
200 pounds of discarded tantalum capacitors for $12.61 per pound. All U.S.
Department of Defense scrapyard personnel handling electronic scrap were
to be trained to perform the 
separation. 
 The Bureau of Mines studied columbium and tantalum occurrences in Alaska.
This study is to serve as a basis for possible future field and laboratory
research.~ Where columbium and tantalum concentrations are relatively high,
these minerals may be recoverable as byproducts of tin, tungsten, gold, or
uranium mining. Approximately 135,000 pounds of Cb2O, are in-