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Platinum is an extremely rare metal, [26] occurring at a concentration of only 0.005 ppm in Earth's crust. [27] [28] Sometimes mistaken for silver, platinum is often found chemically uncombined as native platinum and as alloy with the other platinum-group metals and iron mostly.
Pilanesberg. The Pilanesberg (formerly Pilandsberg[2][3]) is a mountain in the North West Province, South Africa. The mountain is an ancient volcanic structure, circular in shape, that rises from flat surrounding plains. It is formed by three concentric ridges or rings of hills, of which the outermost has a diameter of about 24 km.
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 ...
Found on Earth in trace quantities by Olavi Erämetsä in 1965; so far, promethium is the most recent element to have been found on Earth. [189] 97 Berkelium: 1949 G. Thompson, A. Ghiorso and G. T. Seaborg (University of California, Berkeley) Created by bombardment of americium with alpha particles. [190] 98 Californium: 1950 S. G. Thompson, K ...
A large soot anomaly was also found in cores from the site. [127] [128] Examples of meltglass from Tell Abu Hureyra [129] In 2020, a group led by Andrew M. T. Moore found high concentrations of iridium, platinum, nickel, and cobalt at the Younger Dryas boundary in material from Tell Abu Hureyra. They concluded that the evidence supports the ...
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 ...
Gold nuggetA selection of precious metal elements; gold, silver, platinum, palladium, copper, ruthenium, rhodium, rhenium, osmium, iridiumand mercury. They are labeled and arranged by their location on the periodic table. Precious metalsare rare, naturally occurring metallicchemical elementsof high economic value.
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 ...