Search results
Results from the WOW.Com Content Network
It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish platina, a diminutive of plata "little silver". [ 6 ][ 7 ] Platinum is a member of the platinum group of elements and group 10 of the periodic table of elements.
The Metre Convention was signed on 20 May 1875 and further formalised the metric system (a predecessor to the SI), quickly leading to the production of the IPK.The IPK is one of three cylinders made in London in 1879 by Johnson Matthey, which continued to manufacture nearly all of the national prototypes as needed until the new definition of the kilogram came into effect in 2019.
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
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 ...
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 ...
Stillwater Mining Company is engaged in the development, extraction, processing, refining and marketing of palladium, platinum and associated metals (platinum group metals or PGMs) from a geological formation in the Stillwater igneous complex in south central Montana known as the J-M Reef and from the recycling of spent catalytic converters.
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 ...
Mining industry of Tanzania. Tanzania is a land rich in minerals. Mining makes up more than 50% of the country's total exports, of which a large part comes from gold. The country has gold reserves of 10 million ounces, generating revenue of over a billion USD. [ 1 ] Diamonds are also found in significant amounts.