Solar furnaces using mirrors to concentrate sunlight on a small area do not produce much power - perhaps 1kW per square metre of mirror - but can reach very high temperatures. From the earliest metalworking through to the beginnings of the industrial revolution, metal refining and working was limited by the difficulty of supplying enough heat to the furnace. For a small scale operation - the sort of activity carried out before the industrial revolution - could a solar furnace have been used instead of one using a fuel (usually charcoal) and air mixture?
I'm imagining a sunny hillside with perhaps 10 to 100 polished metal mirrors, perhaps a square metre apiece, aligned by humans running about, all pointing at a small crucible or forge inside as much insulation as could be wrapped around it.
Would it be possible to use that for refining or forging?
I want to ask, over on history stack exchange, whether such an arrangement was ever used, but I thought I'd make a fool of myself asking a question over here before I make a fool of myself asking one over there. Thanks!
Edit: I did find these:
I'm guessing it would have been hard to make a large Fresnel lens until relatively recently. Mirrors are much easier, they have lovely shiny steel armour in many museums, and child labour to polish the metal and align the mirrors would have been cheap in the past. The Woodward forge looks good but the blog says that it hasn't been used for metalwork. Has anyone made this work on a small scale with mirrors?