Non-decimal currency Non-decimal currency A non-decimal currency is a currency that has sub-units that are a non-decimal fraction of the main unit, i.e. the number of sub-units in a main unit is not a power of 10. Today only two countries in the world use non-decimal currencies. Both of these countries are in Africa. These are Mauritania (1 ouguiya = 5 khoums) and Madagascar (1 ariary = 5 iraimbilanja). However these are only theoretically non-decimal, as in both cases the value of the main unit is so low that the sub-unit is too small to be of any practical use and coins
Halfpenny (British pre-decimal coin) Halfpenny (British pre-decimal coin) The British pre-decimal halfpenny (d) coin, usually simply known as a halfpenny (pronounced ), historically occasionally also as the obol, was a unit of currency that equalled half of a penny or of a pound sterling. Originally the halfpenny was minted in copper, but after 1860 it was minted in bronze. It ceased to be legal tender in 1969, in the run-up to decimalisation. The halfpenny featured two different designs on its reverse during its years in circulation. From 1672 until 1936 the image of Britannia appeared on the reverse, and from 1937 onwards the image