100 cp = 10 sp = 1 gp = 1/5 pp
Money in WATERDEEP is, predictably, varied and often exotic. However, like most places in the Realms, Waterdeep coins its own currency, accepts the currency of other lands, and does a fair business in the changing of coins.
However, a gold is a gold is a gold. Most coins in the Realms are similar because trade is so important. A gold coin from a reputable land of origin is probably going to be very similar to a gold coin minted anywhere else. While traders still keep scales, they find it eases trade to put a certain level of trust in certain coinage.
For example, a coin from Cormyr will usually be taken at face value with little fuss because of their strict code of law. Coins from Sembia will probably be taken similarly, as long as they don’t look worn or shaved, because that land has long yearned for the trust necessary to become a military and economic powerhouse.
Ancient coins, odd coins, or coins from suspect lands will undoubtedly cause a trader to reach for his weights.
In Waterdeep, there are two addition coins worth note: the toal and the harbor moon.
The toal is worth 2 gold in Waterdeep. But because its worth is not based on its weight of precious metals, it is worth very little elsewhere. City officials are bound by law to exchange it, so the value of the coin is directly tied to the trust in the government. This is unusual in the Realms.
The harbor moon works on the same system. This part platinum-part electrum coin is worth 50 gold in Waterdeep, though considerably less elsewhere unless the owner expects to be visiting Waterdeep anytime soon. It is used to move expensive good more easily within the city.