Arzinian mines that can be accessed after completing the Between a Rock... Quest. A nearby dwarf will deposit your load of gold in the bank for you, but charges several gold ores. If you wear an activated ring of charos (from the Garden of Tranquillity quest), you can charm him to reduce the fee. But with this you need to mine more gold ores. there's guide on mining gold ores, i just can't remember where it is.