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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 ...
Platinum melts at 1768 °C (3215 °F), even higher than iron. [21] Native South Americans worked with it instead by sintering: they combined gold and platinum powders, until the alloy became soft enough to shape with tools. [25] [26]
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 small box from the burial of the Pharaoh Shepenupet II (died around 650 BC) was found to be decorated with gold-platinum hieroglyphics, [36] but the Egyptians may not have recognised that there was platinum in their gold. [37] [38] First European description of a metal found in South American gold was in 1557 by Julius Caesar Scaliger.
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.
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In late 1826, P.G. Sobolevsky (the father of powder metallurgy in Russia) invented a simple way of processing platinum that prompted the idea to use platinum in coins. The decree of 24 April 1828 A.D. noted that "among the treasures of the Ural Mountains also occurs platinum, which previously was located almost exclusively in South America. For ...
When Willis began marketing his paper, platinum was relatively cheap. By 1907, platinum had become 52 times more expensive than silver. Eastman Kodak and most other producers stopped fabrication of the paper in 1916. Russia controlled 90% of the world platinum supply in World War I and all available platinum was used in the war effort ...