China, gold production

Major producers of gold include the RS A, the United States, the former Soviet Union, Canada, Australia, the People s Republic of China, and Brazil. However, official gold production data from many localities and nations are unreliable, and are usually underreported. Accurate reporting of gold production is needed in order to establish a realistic price for this commodity. 

Arsenic occurs primarily in sulphide minerals associated with copper ores, and to a lesser extent with zinc, lead and gold ores. Arsenic is produced as a by-product of the smelting of these metals. Primary arsenic production has now ceased in the USA and Europe, and most arsenic is now imported from China and Mexico. The volatility of arsenic represents a significant concern, and there is at present no known natural mechanism by which arsenic is immobilized in the environment. Anthropogenic activities account for an input of some 19000 tonnes into the atmosphere, compared with 12000 tonnes from natural processes, such as volcanism and forest fires (Ayres and Ayres, 1996). 

Throughout the history of aviation, the United States has been a leader in research and development of flight instrumentation and avionics. During the Gold War, the Soviet Union and China worked to develop their own systems but lagged behind the United States. China has produced its own avionics but has not found an international market for its products. China has partnered with U.S. companies such as Honeywell and Rockwell Collins to produce avionics. 

Only two beryllium minerals are of commercial importance for the preparation of beryUium metal and its compounds. Bertrandite Be SijOylOH), containing less than 1% Be, is the principal beryUium mineral mined in the USA, while heryl BCjAl lSiOjIg (Figure M16) with 4% Be is the mineral produced in other countries. In the year 2000 the world total mined production was 280 tonnes (counted as beryl-hum), 185 toimes in the USA, 55 tonnes in China and 40 tormes in Russia. About 65% of the world s beryUium resources are concentrated in the United States. The deposits are mainly situated at Gold HiU and Spor Mountain, both in Utah, and on the Seward Peninsula in Alaska [15.3]. 

Arsenopyrite FeAsS is the most important arsenic mineral. As a rule the arsenic-containing ores are mined mainly for their contents of the more attractive metals, gold, silver, copper, lead and zinc. On treatment of the complex ores, arsenic oxide As O is obtained. Reduction with charcoal gives metallic arsenic. The most important commodity is however the oxide. The world production of As Oj was 35000 tonnes in 2001, with China as the largest producer country (16000 tonnes), followed by Chile (8000 tonnes), Mexico and Peru (2500 tonnes each), Kazakhstan and Russia (1500 tonnes each), Belgium and France (1000 tonnes each). 

As a raw material for sulfur, the mineral pyrite FeS is important, but more so in ear-her times than nowadays. It is a brass-yellow mineral with such a brilliant metallic luster that it has been mistaken for gold. It commonly crystallizes in cubes. Pyrite is the most abundant of the sulfide minerals and occurs in all kinds of rocks and coal seams. Pyrite is an important ore of sulfur, less so of iron, and is sometimes mined for the associated gold and copper. In modem sulfur production, China is the only country (among the top producers of the world) whose primary sulfur source is pyrite. 

Cyanide Removal. Cyanide removal from waste liquors in gold processing is being commercialized at the Huang-hua Mountain Gold Plant, near Tian-jin, China (7,22,27,25). Table HI shows the ELM system for the cyanide removal (27), Cyanide can be reduced from about 130 mg/L to 0.5 mg/L with an extraction efficiency of 99.6%, leading to pollution control and productivity increase. In addition to Extractant M and Lan 113-b used by Tm and Zhang (27), an amine extractant, e.g., Alamine (Henkel), and a polyamine surfactant, e.g., EC A 11522 or Paranox 100, could constitute an effective ELM system for the cyanide removal. 

L.P. Yu, Distribution and production of gold resources in China, Chinese metal bulletin, 27(2008), 28-29. 

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