Brass than in brass produced by cementation. These may be "natural alloys" manufactured by smelting zinc rich copper ores in redox conditions. Many have similar tin contents to contemporary bronze artefacts and it is possible that some copper-zinc alloys were accidental and perhaps not even distinguished from copper. However the large number of copper-zinc alloys now known suggests that at least some were deliberately manufactured and many have zinc contents of more than 12% wt which would have resulted in a distinctive golden color. By the 8th–7th century BC Assyrian cuneiform tablets mention the exploitation of the "copper of the mountains"
What the Industrial Revolution Did for Us What the Industrial Revolution Did for Us What the Industrial Revolution Did for Us is a BBC documentary series produced in conjunction with the Open University that examines the impact of the Industrial Revolution on modern society. It was originally broadcast on BBC Two from 7 October to 11 November 2003. Cruickshank travels around Britain to introduce the idea and inventions of the Industrial Revolution that created the modern material world. Cruickshank travels around Britain to introduce the idea and inventions of the Industrial Revolution that created the features of modern working life. Cruickshank travels around Britain to introduce the