I will start at the beginning with the first sort of work. Experienced
miners, when they dig the ore, sort the metalliferous material from earth,
stones, and solidified juices before it is taken from the shafts and tunnels,
and they put the valuable metal in trays and the waste into buckets. But
if some miner who is inexperienced in mining matters has omitted to do this,
or even if some experienced miner, compelled by some unavoidable necessity,
has been unable to do so, as soon as the material which has been dug out
has been removed from the mine, all of it should be examined, and that part of
the ore which is rich in metal sorted from that part of it which is devoid of
metal, whether such part be earth, or solidified juices, or stones. To smelt
waste together with an ore involves a loss, for some expenditure is thrown
away, seeing that out of earth and stones only empty and useless slags are
" copper in wasteinge of it, ar by arte maide freindes, and be not onely an en crease to the
" copper, but further it in smeltinge ; and the rest of the other evill humors shalbe so
" corrected, and their humors so taken from them, that by once rosteinge and once smeltinge
" the ure (which shalbe done in the space of three dayes), the same copper ure shall yeeld us
" black copper." Jochim proposed by ' rostynge ' to be rid of "sulphur, arsineque, and
'* antimony."
