Ponies on the Isle of Yore and its vicinity use a variety of currencies and media of exchange.
exchange rates table here
Bits
Bits are a common form of currency taking their name and physical appearance from an ancient Equestrian currency. Many of the original coins are still around, due to long-lasting anti-wear enchantments. Although originally fiat currencies, their distinctive enchantments are very difficult to duplicate, and there is an effectively limited supply of old bits. The city of Docktown has recreated an approximation of these enchantments, and New Equestria claims to have retained knowledge of the numismatic magic from Golden Age Equestria. Both of those entities mint modern bits.
Docktown Bits
The Docktown Bit is the official currency of Docktown. It comes as coins of various denominations, and as paper money backed by coins in banks. The currency is used throughout the Eastern Dusts, particularly in the Southern area, and increasingly in all settlements served by the Docktown Railroad, which uses it exclusively.
New Equestrian Bits
Old Bits
These coins represent bits minted by pre-Catastrophic civilizations. Old Bits have steadily deflated over time as anti-wear enchantments fade, they are lost or hoarded, and so on. The have the advantage of being accepted almost everywhere.
Bucks
Bucks were the historical currency of most of Ponyland. Bucks were mostly circulated as paper money.
Springvale Buck
Pony Republic Buck
Yore Valley Buck
Jangles
Jangles were a historical currency in parts of Ponyland and in some other regions of Equus.
Precious Metals