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Others reduce the ore in iron pans as next described. They lay small pieces of dry wood alternately straight and transversely upon bricks, one and a half feet apart, and set fire to it. Near it they put small iron pans lined on the inside with lute, and full of broken ore; then when the wind blows the flame of the fierce fire over the pans, the bismuth drips out of the ore; wherefore, in order that it may run, the ore is stirred with the tongs ; but when they decide that all the bismuth is exuded, they seize the pans with the tongs and remove them, and pour out the bismuth into empty pans, and by turning many into one they make cakes. Others reduce the ore, when it is not mixed with cadmia,60 in a furnace similar to the iron furnace. In this case they make a pit and a crucible of crushed earth mixed with pulverised
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charcoal, and into it they put the broken ore, or the concentrates from washing, from which they make more bismuth. If they put in ore, they reduce it with charcoal and small dried wood mixed, and if concentrates, they use charcoal only; they blow both materials with a gentle blast from
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