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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 ...
The earliest known powder metallurgy, and earliest working of platinum in the world, was apparently developed by the cultures of Esmeraldas (northwest Ecuador) before the Spanish conquest [17] Beginning with the La Tolita culture (600 BC – 200 CE), Ecuadorian cultures mastered the soldering of platinum grains through alloying with copper ...
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.
1912 – Stainless steel invented by Harry Brearley; 1916 – Method for growing single crystals of metals invented by Jan Czochralski; 1919 – The merchant ship Fullagar has the first all welded hull. 1924 – Pyrex invented by scientists at Corning Incorporated, a glass with a very low coefficient of thermal expansion
One of the largest bullion coins in the world was the 10,000-dollar Australian Gold Nugget coin minted in Australia, which consists of a full kilogram of 99.9% pure gold. In 2012, the Perth Mint produced a 1-tonne coin of 99.99% pure gold with a face value of $ 1 million AUD, making it the largest minted coin in the world with a gold value 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
The most notable examples are the Platinum cat, [8] and Platinum Noble by the Isle of Man, Canadian Platinum Maple Leaf, [9] Chinese Platinum Panda and Australian Platinum Koala. [citation needed] The minting of a trillion-dollar platinum coin was proposed as a solution to the 2023 United States debt-ceiling crisis.
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.