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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 ...
The first plastic made from synthetic components, it was developed by Leo Baekeland in Yonkers, New York, in 1907, and patented on December 7, 1909. [ 3 ] Bakelite was one of the first plastic-like materials to be introduced into the modern world and was popular because it could be moulded and then hardened into any shape.
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 ...
During the Early horizon, advances in metal working produced spectacular and characteristic Andean gold objects made by the joining of smaller metal sheets, and also gold-silver alloy appeared. Two traditions seem to have developed alongside each other – one in northern Peru and Ecuador, and another in the Altiplano region of southern Peru ...
1000 BC – The Phoenicians introduce dyes made from the purple murex. [1] 3rd century BC – Wootz steel, the first crucible steel, is invented in ancient India; 50s BC – Glassblowing techniques flourish in Phoenicia; 20s BC – Roman architect Vitruvius describes low-water-content method for mixing concrete
Early coinage made from metal came into use during the Axial Age in the Greek world, in northern India, and in China, as coins became a widespread embodiment of money. [2] Bronze, gold, silver and electrum (a naturally occurring pale yellow mixture of gold and silver that was further alloyed with silver and copper) were used.
In order to separate the gold and silver, however, the Romans would granulate the alloy by pouring the liquid, molten metal into cold water, and then smelt the granules with salt, separating the gold from the chemically altered silver chloride (Tylecote 1962). They used a similar method to extract silver from lead.
Before the early 1800s, aluminum had not been produced as an isolated metal. It wasn't until 1825 that; Hans Christian Ørsted discovered how to create elemental aluminum via the reduction of aluminum chloride. Since aluminum is a light element with good mechanical properties, it was widely sought to replace heavier less functional metals like ...