|This article is about an older version of DF.|
The game's currency is measured in "☼", called "dwarfbucks" or "db's" by some players. Each item has a specific trade value in ☼.
When the dwarven economy sets in, some coins will have monetary value in addition to their trade value; copper coins are worth 1☼, silver coins are worth 5☼ and gold coins are worth 15☼.*
Independent of this, the value of a coin of any other metal when used in trade, or for collectors coins* sold in shops, is 1/50th the material multiplier of the metal. Since you get 500 coins per bar of metal, this is equivalent to an item value of 10.
(* Coins of metal other than copper, silver or gold are sold in shops.)
Using coins as a trade good is not advisable as they have no quality levels. Allowing coinage in general circulation is not recommended as it aids nothing and dwarves tend to spend considerable time moving them around pointlessly.
Dwarven coins are minted at the Metalsmith's forge.
Coins have little value in fortress mode and do not benefit the economy in any way, nor do they make anyone happier, but they do lead to massive slowdowns both in cpu terms and in terms of what your dwarves can accomplish.