Monetary System

Most DnD games require some sort of monetary system. This one is a synthesis from several sources, and you are welcome to use it.

You Have Its Worth (cp) Its Worth (sp) Its Worth (gp) Source
Shell .01 .001 .0001 Shell Money, Wampum
Lead Bead .01 .001 .0001 Dark Sun
Ceramic Bit (bit) .1 .01 .001 Dark Sun
Ceramic Piece 1 .1 .01 Dark Sun
Copper Piece (cp) 1 .1 .01 All Editions
Bronze Piece 1 .1 .01  
Silver Piece (sp) 10 1 .1 All Editions
Electrum Piece (ep) 50 5 .5 DnD 1, 2 and 5
Gold Piece (gp) 100 10 1 All Editions
Steel Piece 100 10 1 Dragonlance
Cow 1000 100 10 PHB5p157
Ox 1500 150 15 PHB5p157
Tilfenim Piece 2500 250 25 Gary Gygax's World Builder
Mithril Piece 3000 300 30 Gary Gygax's World Builder
Adamantium Piece 4500 450 45 Gary Gygax's World Builder
Xagium Piece 5000 500 50 Gary Gygax's World Builder
Platinum Piece (pp) 10,000 1000 100 All Editions
Oracalium Piece 10,000 1000 100 Gary Gygax's World Builder
Astral Diamond* (ad) 1,000,000 100,000 10,000 4th Edition
Copper pieces (cp) are the most common coin among laborers and beggars.

The common people of the world deal in silver pieces (sp).

Merchants and adventurers use the gold piece (gp) as the standard unit of currency for most transactions. Large transactions might be handled in gems, but the value is always measured in gold.

Check tvtropes.org for more on the gold / silver / copper standard.

Electrum pieces (ep) and platinum pieces (pp) originate from fallen empires and lost kingdoms. They sometimes arouse suspicion and skepticism when used in transactions.

Many ancient empires minted platinum pieces, and merchants accept them, even if most people never see them.

A coin is about an inch across, and weighs about a third of an ounce (50 coins to the pound).
* Astral Diamonds weigh 500 to the pound.

Campaign Coins
Converting a D&D economy to the silver standard
Currency by Old Guy Gaming
My Beef With Tin Pieces by Roger Wilcox

Any additions, comments or questions for the webmaster?