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The specific layer he found, named the Merensky Reef, contains around 75% of the world's known platinum. [32] [33] The large copper–nickel deposits near Norilsk in Russia, and the Sudbury Basin, Canada, are the two other large deposits.
Sican tumi, or ceremonial knife, Peru, 850–1500 CE. Metallurgy in pre-Columbian America is the extraction, purification and alloying of metals and metal crafting by Indigenous peoples of the Americas prior to European contact in the late 15th century. Indigenous Americans had been using native metals from ancient times, with recent finds of ...
Rank Country/Region Platinum production (kilograms) Year World 180,000 2019 1: South Africa: 130,000 2019 2: Russia: 22,000 2019 3: Zimbabwe: 15,000 2019 4: Canada
Metals of antiquity. German amulet to protect against disease (18th century); it is made from an alloy of the seven alchemical metals: lead, tin, iron, gold, copper, mercury and silver. The metals of antiquity are the seven metals which humans had identified and found use for in prehistoric times in Africa, Europe and throughout Asia: [1] gold ...
Naturally occurring platinum and platinum-rich alloys were known by pre-Columbian Americans for many years. [5] However, even though the metal was used by pre-Columbian peoples, the first European reference to platinum appears in 1557 in the writings of the Italian humanist Julius Caesar Scaliger (1484–1558) as a description of a mysterious metal found in Central American mines between ...
In 2019, the country was the world's largest producer of platinum; [8] the world's largest producer of chromium; [9] the world's largest producer of manganese; [10] the 2nd largest world producer of titanium; [11] the world's 11th largest producer of gold; [12] the 3rd worldwide producer of vanadium; [13] the 6th largest world producer of iron ...
Only gold, silver, copper and the platinum group occur native in large amounts. [citation needed] Over geological time scales, very few metals can resist natural weathering processes like oxidation, so mainly the less reactive metals such as gold and platinum are found as native metals. The others usually occur as isolated pockets where a ...
The International Prototype of the Kilogram (referred to by metrologists as the IPK or Le Grand K; sometimes called the ur -kilogram, [ 1 ][ 2 ] or urkilogram, [ 3 ] particularly by German-language authors writing in English [ 3 ][ 4 ]: 30 [ 5 ]: 64) is an object whose mass was used to define the kilogram from 1889, when it replaced the ...