Silver ore

Silver is formed in nature as argentite. AgjS and horn silver. AgCl. The extraction of silver depends upon the fact that it very readily forms a dicyanoargentate(I) complex, [Ag(CN)2] (linear), and treatment of a silver ore with aqueous cyanide ion CN extracts the silver as this complex. The silver is then displaced from the complex by zinc ... 

The most important body of primary silver ore in the United States in the 1990s is located in Silver Valley, the Coeur d Alene Mining District of Shoshone County, Idaho, which produces >200 t/yr of silver. The main ore mineral is tetrahedrite [12054-35-2] associated with sulfides of lead, copper, iron, and 2inc. 

Troy Lincoln, Mont. ASARCO Incorporated copper—silver ore, concentrated 18... 

Chloridizing. Silver ores are chloridized successfully in rotary kilns. Temperatures must be closely controlled between 1030 and 1090 K. 

Gold and silver (o) chloridizing roast of gold-silver ore, and (b) removal of arsenic... 

Rosch-erz. -gewachs, n. brittle silver ore, stephanite. -heit, /. brittleness, etc. (see rosch). 

The technologies involved in the minerals processing industry can be broken down into those where the desired metal component is in high concentration, such as scrap iron, iron ore, phosphate ore, and bauxite, and those where the concentration of the valuable constituent is low, such as gold and silver ore, lean copper ore, and certain types of scrap and wastes. 

Matsukuma, T. (1985) Gold and silver in the Kuroko deposits. In Mining and Metallurgical Institute of Japan (ed.). Gold and Silver Ore in Japan, 155-193 (in Japanese). 

Nishiwaki, C., Matsukuma, T. and Urashima, Y. (1971) Neogene gold-silver ores in Japan. Mining Geology Special Issue, The Society of Mining Geologists of Japan, 3, 409-417. 

Ono, S. and Sato, J. (1995) Gold and silver ores from the Ezuri Kuroko ore deposits, Akita Prefecture, Japan. Assoc. Mineral Petrol Econ. Geol, 90, 268-279 (in Japane.se with English abst.). 

Watanabe, K. and Nagai, S. (1986) Regional aleration in and around the Rendaiji gold-silver ore deposits, Shizuoka Prefecture. J. Miner. Soc. Jpn., 17, 69-74 (in Japanese with English abst.). 

Yoneda, T. and Watanabe, T. (1981) Clay minerals in the gold silver ore of the Chuetsu-hi vein of the Todoroki mine, Hokkaido, Japan. Soc. Mining Geologists Special Issue, 10, 143-150 (in Japanese with English abst.). 

Precious metals such as silver and gold, which are seldom oxidized even at high temperatures, are often refined by cupellation, a process for removing from them base metal impurities such as lead and tin, with which they are associated in many ores. Hot lead and tin are easily oxidized. In the cupellation process, a crude, impure precious metal is placed in a shallow cup or crucible made of bone ash, known as a cupel, and is then heated by a blast of hot air. At high temperatures, the base metal impurities are oxidized by oxygen in the hot air, and the oxides thus formed are absorbed by the porous bone ash. The Chaldeans are said to have been the first to have utilized (ca. 2500 b.c.e.) cupellation to remove lead and purify silver from lead-silver ores. 

Wulfenite and minetizit are mainly associated with oxide lead silver ores. Very little to no research data are available on these two minerals. Most recently, research work was carried out on these minerals using natural ore. It has been demonstrated that wulfenite and minetizit can be recovered using sulphidization and modified xanthate. 

Oxide lead silver ores are very rare and there is only one operating plant in the world treating this type of ore. The process development and plant design was accomplished during 2005-2006 and has been in operation since December 2007 [12,13], There are several ore types present in the ore. 

Reagent scheme used for heneficiation of oxide lead silver ore (Peru operation)... 

Occurrence. Nearly all the silver ores are compounds of silver with sulphur and the neighbours in the Periodic Table arsenic, antimony and bismuth (argentite Ag2S, the most common silver compound, pyrargyrite Ag3SbS3, proustite Ag3AsS3). Other silver minerals include the halides. Silver is found sometimes as the free metal. Secondary silver (from catalysts, scraps, photographic films, etc.) is an important source. 

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