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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 ...
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 ...
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 ...
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.
Gold double pendant, Panama, Veraguas, 11th–16th century AD. Gold, copper and tumbaga objects started being produced in Panama and Costa Rica between 300–500 CE. Open-molded casting with oxidation gilding and cast filigrees were in use.
Other terms often used for printed engravings are copper engraving, copper-plate engraving or line engraving. Steel engraving is the same technique, on steel or steel-faced plates, and was mostly used for banknotes, illustrations for books, magazines and reproductive prints, letterheads and similar uses from about 1790 to the early 20th century, when the technique became less popular, except ...
Native copper nugget from glacial drift, Ontonagon County, Michigan. An example of the raw material worked by the people of the Old Copper Complex. The Old Copper complex or Old Copper culture is an archaeological culture from the Archaic period of North America's Great Lakes region. Artifacts from some of these sites have been dated from 6500 ...
The most commonly produced plastic consumer products include packaging made from LDPE (e.g. bags, containers, food packaging film), containers made from HDPE (e.g. milk bottles, shampoo bottles, ice cream tubs), and PET (e.g. bottles for water and other drinks). Together these products account for around 36% of plastics use in the world.