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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 is accidentally synthesized in 1872 by German chemist Eugen Baumann ...
Over the K&T era multiple wire types evolved. Early wiring was insulated with cotton cloth and soft rubber, while later wiring was much more robust. Although the actual wire covering may have degraded over the decades, the porcelain standoffs have a nearly unlimited lifespan and will keep any bare wires safely insulated.
The wire is coated with a range of polymeric insulations, including varnish, rather than the thicker plastic or other types of insulation commonly used on electrical wire. [5] High-purity oxygen-free copper grades are used for high-temperature applications in reducing atmospheres or in motors or generators cooled by hydrogen gas.
The name is mostly applied informally to compositions between 20–80% gold and 80–20% silver, but these are strictly called gold or silver depending on the dominant element. Analysis of the composition of electrum in ancient Greek coinage dating from about 600 BC shows that the gold content was about 55.5% in the coinage issued by Phocaea .
Jewelry wire is wire, usually copper, brass, nickel, aluminium, silver, or gold, used in jewelry making. Wire is defined today as a single, usually cylindrical, elongated strand of drawn metal . However, when wire was first invented over 2,000 years BC, it was made from gold nuggets pounded into flat sheets, which were then cut into strips.
Copper wire can be hammered quite thin. Brass wire is a little stiffer than copper, but it can be manipulated very easily. Sterling silver is soft enough to manipulate, but holds its shape well once it has been formed. Gold-filled wire is made by fusing a layer of 12-or 14-karat gold to a supporting material. Silver-filled wire is made in the ...
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 ...
By careful treatment, extremely thin wire can be produced. Special purpose wire is however made from other metals (e.g. tungsten wire for light bulb and vacuum tube filaments, because of its high melting temperature). Copper wires are also plated with other metals, such as tin, nickel, and silver to handle different temperatures, provide ...