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  2. Timeline of plastic development - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_plastic...

    Parkesine, the first member of the Celluloid class of compounds and considered the first man-made plastic, is patented by Alexander Parkes. [4] 1869: John Wesley Hyatt discovers a method to simplify the production of celluloid, making industrial production possible. 1872: PVC was accidentally synthesized in 1872 by German chemist Eugen Baumann ...

  3. Metals of antiquity - Wikipedia

    en.wikipedia.org/wiki/Metals_of_antiquity

    The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...

  4. Coinage metals - Wikipedia

    en.wikipedia.org/wiki/Coinage_metals

    Many coins throughout history were made of gold, silver and copper. Silver: Gold: Iron: Numerous Chinese cash coins were made of iron, with the first being issued by the Han dynasty in 118 BCE. From 1942 through 1952, some of the Swedish krona coins – such as the 1, 2 and 5 öre – were made of iron. Lead: Most commonly seen in southeast ...

  5. Bakelite - Wikipedia

    en.wikipedia.org/wiki/Bakelite

    The retro appeal of old Bakelite products has made them collectible. [4] The creation of a synthetic plastic was revolutionary for the chemical industry, which at the time made most of its income from cloth dyes and explosives. Bakelite's commercial success inspired the industry to develop other synthetic plastics.

  6. Plastic - Wikipedia

    en.wikipedia.org/wiki/Plastic

    Plastic consumption differs among countries and communities, with some form of plastic having made its way into most people's lives. North America (i.e. the North American Free Trade Agreement or NAFTA region) accounts for 21% of global plastic consumption, closely followed by China (20%) and Western Europe (18%).

  7. Metallurgy during the Copper Age in Europe - Wikipedia

    en.wikipedia.org/wiki/Metallurgy_during_the...

    Reconstruction of Ötzi's copper axe (c. 3300 BCE). The Copper Age, also called the Eneolithic or the Chalcolithic Age, has been traditionally understood as a transitional period between the Neolithic and the Bronze Age, in which a gradual introduction of the metal (native copper) took place, while stone was still the main resource utilized.

  8. Group 11 element - Wikipedia

    en.wikipedia.org/wiki/Group_11_element

    Copper occurs in its native form in Chile, China, Mexico, Russia and the USA. Various natural ores of copper are: copper pyrites (CuFeS 2), cuprite or ruby copper (Cu 2 O), copper glance (Cu 2 S), malachite (Cu(OH) 2 CuCO 3), and azurite (Cu(OH) 2 2CuCO 3). Copper pyrite is the principal ore, and yields nearly 76% of the world production of copper.

  9. Pinchbeck (alloy) - Wikipedia

    en.wikipedia.org/wiki/Pinchbeck_(alloy)

    It was invented in the early 18th century by Christopher Pinchbeck (died 1732), a London clock- and watch-maker. [1] Since gold was only sold in 18-carat quality at that time, the development of pinchbeck allowed ordinary people to buy gold 'effect' jewellery on a budget. The inventor allegedly made pinchbeck jewellery clearly labelled as such.