The common currency within all known and stable cities.
Denna comes in the form of small paper squares, made of a very specific plant fiber and dyed with a uniquely mixed combination of orange and red dyes. The value of the materials used to make each note is considered equally valuable and held against the cost of creation.
Denna is marked in denominations of 1, 5, 10 and 100 bills, each with a thicker paper weight as value increases. Only larger businesses within Duno and the Halzin Nations ever transfer 100 bill Denna, most common folks will only travel with 1, and 5 note squares.
Smaller towns commonly have their own paper notes that are equal in value to Denna, and used in place of physical money when conducting business. Voucher notes are then in turn traded in for actual Denna when leaving the town via a well maintained exchange location. This system protects against targeted theft and allows smaller locations to monitor income within their boarders.