BISMUTH ORES (EN: bismuth ores; DE: Wismuterze; FR: minerais bismuthiques; ES: minerales de bismuto; RU: висмутовые руды) are the natural mineral formations, which are containing bismuth in such quantities, with which there is economically expedient its extraction using the modern methods for the production. Besides the bismuth ores proper, they distinguish the bismuth-containing ores, namely, the ores of the nonferrous and precious metals, within which bismuth is the accompanying or one of the constituent components.
Bismuth is located within the ores mainly in the form of its own minerals, and in the lesser degree, in the form of the impurity within the galena, and within the antimony sulfosalts. Within the nature, there are known more than 60 bismuth ore minerals, of which the major minerals are: the native bismuth (contains 95.9-99.9% of Bi), bismuthinite (81.3% of Bi), cosalite - Pb2Bi2S5 (42% of Bi), aikinite - CuPbBiS3 (36.3% of Bi), tetradymite - Bi2Te2S (59.27% of Bi), tellurobismuthite - Bi2Te3 (52% of Bi), bismite - Bi2O3 (89.7% of Bi), bismutite - Bi2CO3(OH)4 (76.5-91.4% of Bi). Within the certain deposits, there acquire the major significance within the bismuth ores the relatively rare minerals: berryite - (Cu,Ag)3Pb2Bi5S11 (51% of Bi), krupkaite - CuPbBi3S6 (57.4% of Bi), pavonite - (Ag,Cu)(Bi,Pb)3S5 (62.5-66.7% of Bi), and others. The accompanying components of the bismuth ores proper are Pb, Cu, Ag, Au, Co, Ni. Among the deposits of the bismuth ores, they distinguish endogenous and exogenous.
|(Table) The dynamics of the production of bismuth within the industrially developed capitalistic and developing countries, tonnes|
|1The ore. 2The concentrate. 3The data on the export.|
The main endogenous deposits of the bismuth ores are the postmagmatic deposits, which are genetically associated with the granitoid complexes. There have the major significance the bismuth-containing ores (0.001-0.1% of Bi) of the tungsten, tin, copper, gold ore, and lead-zinc deposits, mainly of the greisen, skarn, and high-temperature hydrothermal groups. These deposits are: the greisen-wolframite deposits within the USSR (Central Kazakhstan, Eastern Transbaikalia), China (Jiangxi Province, Hunan); the skarn-scheelite deposits within the USSR (Bogutinskoe deposit, Vostok-2), and within the South Korea (Sandon); the copper-skarn deposits within the USA (the Montana, Utah, and California states); the skarn-polymetallic deposits within the USSR (Central Asia, the Primorje - Dalnegorsk group of the polymetallic deposits) and Mexico; the tin sulfide deposits within Bolivia (Tasna, Caracoles, Esmoraca); the copper with gold ore deposits within Australia (the Tennant Creek, Warrego, Juno, and other regions); the copper and lead deposits within Japan (the south-east and north of the Honshu island); the polymetallic deposits within Peru (Cerro de Pasco). The bismuth ores proper contain more than 0.2% of Bi; the deposits of these ores are rare and relatively small according to the scales. Under the exogenous conditions during the destruction of the bedrock deposits, there emerge the small eluvial, diluvial, and less often diluvial-alluvial placers.
During the beneficiation of the bismuth ores, the minerals of bismuth accumulate within the copper and (or) lead concentrates, because their flotation properties are similar to such properties of the Pb and Cu sulphides. In case of the low contents of the Pb and Cu sulphides within the ores (or in case of the high contents of Bi), there is obtained the bismuth concentrate proper (with the content of Bi of more than 0.6%). The bismuth-containing products (the bismuth and lead concentrates, the dusts and sludges of the copper production, in the lesser extent of the tin and molybdenum production) are concentrated at the enterprises, which are producing lead, where they obtain the metallic bismuth along the way during the refining of lead. They perform the removal of bismuth from the lead either using the addition of Ca and Mg into the molten lead, and bismuth forms the refractory compounds with these additives, or using the electrolysis within the silicofluoride electrolyte (Pb precipitates onto the cathode, Bi transitions into the sludge).
The total worldwide accounted (1980) reserves of bismuth within the ores (without the socialistic countries) are evaluated at 140 thousand tonnes (in terms of the extractable metal), including (thousand tonnes): within Japan - 23, within Australia - 17, within Bolivia - 14, within USA - 9, within Mexico - 5, within Canada - 5, within Peru - 4.5, and also within the South Korea, and France; the potential resources amount to 91 thousand tonnes. Among the large producing countries, only Bolivia extracts bismuth specially from the bismuth ores, with the high content of Bi; within other countries, the bismuth is extracted along the way, for example, within Peru - during the development of the lead-zinc ores, within Mexico - during the development of the lead ores, within Australia - during the development of the copper-gold ores.
The extraction of the bismuth ores (without the socialistic countries) is evaluated at approximately 4 thousand tonnes (1980). The main extracting countries are Australia, Japan, Peru, Mexico, and Bolivia (see the Table).
|A a||B b||C c||D d||E e||F f|
|G g||H h||I i||J j||K k||L l|
|M m||N n||O o||P p||Q q||R r|
|S s||T t||U u||V v||W w||X x|
|Y y||Z z|