Ducats are the unit of money used in Dwarf Hammer. The player's starting ducats are inherited from his parents, which are of course dependent upon the wealth of the grandparents created by the player.
Most creatures don't carry their ducats on them, but rather their checkbooks. Ducats are not earned by killing things, but by selling loot and gems (which can be created by killing diamond creatures). Your ducats can be invested in the bank, the stock market, or a mutual fund.