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Platinum is a chemical element; it has symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish platina, a diminutive of plata "silver". [7] [8] Platinum is a member of the platinum group of elements and group 10 of the periodic table of ...
Tennant had been working on samples of South American platinum in parallel with Wollaston and discovered two new elements, which he named osmium and iridium, and published the iridium results in 1804. [115] Collet-Descotils also found iridium the same year, but not osmium. [85] 45 Rhodium: 1804 H. Wollaston: 1804 H. Wollaston
William Willis Jr. (1841–1923) [1] is a British inventor who developed the platinum printing process, an early form of photography, based on the light sensitivity of platinum salts, originally discovered by John Herschel. [2] William Willis was the son of British engraver of landscapes, and inventor of the anilin printing, process William Willis.
A wrought iron ruler, the Toise of Peru, also called Toise de l'Académie, was the French primary standard of the toise, and the metre was officially defined by an artifact made of platinum kept in the National Archives. Besides the latter, another platinum and twelve iron standards of the metre were made by Étienne Lenoir in 1799.
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 ...
Platinum was first used for minting coins in Spanish-colonized America. Following the discovery of platinum in gold rocks, the Spaniards were unable to use it for a long time because they had no technology for processing this metal. The then-cheap platinum was used for various kinds of frauds, such as substituting it for the more expensive silver.
The measurement of sales of popular music starts high relative to the wedding anniversary scale, concentrating on gold and platinum (see gold album).Likewise, credit card companies usually have a "gold card" and a "platinum card" (many formerly had a "silver card" then followed by a "gold card", but due to similarity in appearance between silver and platinum these were often discontinued with ...
Heating this platinum at high temperatures leaves behind thin filaments of platinum coated with pure graphite. By September 1881 he had achieved a successful version of this the first synthetic filament. The light bulb invented by Cruto lasted five hundred hours as opposed to the forty of Edison's original version.