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This alchemical symbol for platinum was made by joining the symbols of silver and gold . Antonio de Ulloa is credited in European history with the discovery of platinum. In 1735, Antonio de Ulloa and Jorge Juan y Santacilia saw Native Americans mining platinum while the Spaniards were travelling through Colombia and Peru for eight years. Ulloa ...
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 ...
True chemical analyses were made in the 18th century, [5] and in 1772 Antoine Lavoisier demonstrated that diamond, graphite, and charcoal are all composed of the same substance. [1] In 1787, de Morveau, Fourcroy, and Lavoisier listed carbon (in French, carbone) as an element, distinguishing it from coal (in French, charbon). [1] 29 Copper: 9000 BC
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 ...
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 ...
2004: First podcast, invented by Adam Curry and Dave Winer, is a program made available in digital format for download over the Internet and it usually features one or more recurring hosts engaged in a discussion about a particular topic or current event. [545] [546] [547] 2005: YouTube, the first popular video-streaming site, was founded
In the New World however, certain Andean cultures recognized platinum as a separate metal and were able to incorporate it into jewellery, such as through sintering it with gold. [71] Jadeite funerary jewellery from Tomb 1 of Structure VII of Calakmul, thought to belong to Yuknoom Tookʼ Kʼawiil. Late Classic (660 to 750 AD).