Coinage

Most trade among commoners is conducted through barter, however metal coinage is an institution established by many governments.  In some areas, metal coinage can be meaningless, as the residents prefer to be paid in service or goods rather than coins they cannot use (without travelling great distances).

Coins of any type have the same weight. 50 coins = 1 pound.

*Titanium coins are a core of titanium with a coating of white gold

A good article on the subject of D&D economics

Commodities

Metals: Iron, Copper, Lead, Tin, Zinc, Silver, Gold (Eastern Only:) Mercury, Bauxite, Nickel

Minerals: Salt, Waxes (Eastern Only:) Coal, Natural Gas, Oils

Fruits & Vegetables: Grapes, Apples, Pears, Peaches, Olives (Northern Only:) Oranges, Bananas

Plant Products (food): Barley, Corn, Wheat, Tea, Coffee, Sugar, Oils (Eastern Only:) Rice, Cocoa

Plant Products (non-food): Cotton, Lumber, Waxes (Eastern Only:) Latex

Animal Products (food): Beef, Poultry, Lamb/Mutton, Pork, Fish, Shrimp, Honey, Oils

Animal Products (non-food): Wool, Hides, Waxes (Eastern Only:) Chitins