As noted, community currencies have many different design features. One of the most basic of these is the ‘denomination’: the proper description of a currency amount, expressed through a range of different transaction media.
Denomination differs from unit of account in that it describes the quantities in which a currency can really be obtained – for example the currency’s physical notes or coins. Unit of account, on the other hand, refers to the standard numerical unit of measurement that enables uniform interpretation of value and cost, such as dollar, hour or ounces of gold. This difference between the unit of account and denomination is best illustrated through practical examples.
The Brixton Pound uses pound sterling as the unit of account, but it is denominated in B£. For the Makkie, the unit of account is time, and it is denominated in full and half hours. Alongside any decisions made about the denomination and unit of account of a currency, the transaction media must be considered.
It is in the field of transaction media that community currencies are typically more innovative then conventional currencies – and have introduced systems such as the Brixton Pound’s ‘pay-by-text’, before many users of mainstream money were even aware of the idea of mobile payments.
Typically, complementary currencies will use one or a combination of the following transaction media: - papernotes - coins - tokens - vouchers - cheques - ‘show’ cards (presented at the point of sale) - ‘swipe’ cards - ‘smart’ cards with various functionalities - RFID chips embedded in cards or other devices - barcodes - QR-codes - SMS (short message service) - Smart device apps
# Bitcoin
Perhaps the most well-known complementary currency in use today, Bitcoin is a digital payment system. The first allocation, or ‘mining’, and consecutive transfer of coins is independent of any central authority or regulation. Bitcoins are transferred through a computer or smartphone without an intermediate financial institution.
The table below gives examples of complementary currencies active in Europe and further afield, showing the range of media used to serve various functions.