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Prior to this invention, mirror plates, made from blown "sheet" glass, had been limited in size. De Nehou's process of rolling molten glass poured on an iron table rendered the manufacture of very large plates possible. [58] This method of production was adopted by the English in 1773 at Ravenhead. The polishing process was industrialized ...
From these experiments he classified substances into two categories: "electrics", like glass, resin and silk, and "non-electrics", like metal and water. Although Gray was the first to discover and deduce the property of electrical conduction, he incorrectly stated that "electrics" conducted charges while "non-electrics" held the charge.
Chalcolithic Age (copper age) beginning about 7,000 years ago: copper, gold, silver, mercury. In the early Bronze Age, lead was used with antimony and arsenic. [2] The use of meteoric iron–nickel alloy has been traced as far back as 3500 BC. Iron Age, Ancient Near East (1300–600 BC), India (1200–200 BC), Europe (1200 BC – 400 AD).
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 ...
Fool's gold – a mineral, iron disulfide or pyrite; can form oil of vitriol on contact with water and air. Fulminating silver – principally, silver nitride, formed by dissolving silver(I) oxide in ammonia. Very explosive when dry. Fulminating gold – a number of gold based explosives which "fulminate", or detonate easily.
5. Brillo Pads. Aluminum was the wonder metal of the early 20th century. One popular use for aluminum was as lightweight cookware to replace heavy cast-iron pans, but unfortunately, aluminum pots ...
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 ...
10th century BC – Glass production begins in ancient Near East; 1st millennium BC – Pewter beginning to be used in China and Egypt; 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 ...