A Goldsmith’s Furnace would allow Coins the be smelted into bars and back with minimal or no loss. This would come in handy if you get rich enough to have a full treasury and wish to condense your excess gold and silver coins into bars. I could also see a more ornate variation offered in Bazaar.
I think it should only work with gold and silver and probably require the player reach Lvl. 60.
I do not understand what you are asking for here. You can smelt 30 gold coins into 1 gold bar in a furnace and you can craft 30 gold coins from 1 gold bar at a casting table. There is no loss.
Just tested it… Dang you are right. Apparently I was working on either Obsolete or just plain wrong data. Sorry for any inconvenience I caused.
There’s certainly room for more items crafted from gold and silver. Silver weapons or augments being more effective against werehyenas for instance much like star metal against golems.
Could even be more building tiers using hardened steel and star metal for reinforcements along with adding gold or silver for looks or other properties.
Maybe we’ll get a Trumpian dlc where all the building pieces are made of gold. Golden towers as far as the engine can render.
No inconvenience, we are happy having you around fellow exile 
.