Hmm, gold ingots sell for 608 trias (which mean 208 profit for the smelter) or am I missing something?
Anyway, Donari, once she joined the Imperial Trades, tried to raise the price to 500 trias as mentioned before. This resulted in the general community doing acts of vandalism (such as putting garbage in the furnace to stop us from smelting), hating us and doing threats of boycotting (and doing bad publicity of) our steel business. So, I agree, the gold smelters are, even if just for their agenda on keeping the 400 price at all costs, being unfair (a funny demonstration of how economic interests bring a community together). I doubt you'll have much luck in getting the 500 trias price. Either the seller already has such conviction and will put himself through the pains of "defying" the gold smelters, or most of them will simply wait for some other miner to show up and buy his ores. Nevertheless, good luck on that.
On the furnaces case, I agree, we could use another economic center, off Ojaveda and Hydlaa.