Draco
Adida
"One gold piece is worth ten silver pieces, the most prevalent coin among commoners. A silver piece buys a laborer’s work for half a day, a flask of lamp oil, or a night’s rest in a poor inn.How many days of unskilled labor is a GP worth? Because in 3.5 it's like two weeks pay.
One silver piece is worth ten copper pieces, which are common among laborers and beggars. A single copper piece buys a candle, a torch, or a piece of chalk."