*a note is posted in the Surge beneath the first one, this one in neat, precise writing*
I've seen Copper go for as much as a hundred true a bar - less for the unrefined product, of course. Tin, similar figures.
As for the miners... well, best to seek them out yourself. If you wish a tour, though, sir Dwarf, seek out Kell Ereptor. Or, more accurately, put out word that you wish to meet him, and you may.