Commodity money cans or foil pouches of mackerel fish fillets, which have a fairly standard cost and are easy to store. These may be exchanged for many services in prisons where personal possession of currency is prohibited. In situations where the commodity is metal, typically gold or silver, a government mint will often coin money by placing a mark on the metal that serves as a guarantee of the weight and purity of the metal. In doing so, the government will often impose a fee which is known as seigniorage. The role of a mint and of coin differs between commodity money
Five Ways to Save the World Five Ways to Save the World Five Ways to Save the World is a British documentary film on environmental issues related to climate change, released in 2006. The film was made by Karen O'Connor, for the big screen and was shot in the English language to reach an international audience. It includes interviews with five environmental scientists and experts including Paul Crutzen, James Roger Angel, John Latham, Ian Jones, and Klaus Lackner. The "five ways" proposed are geoengineering techniques: Since the first three methods do not remove carbon dioxide from the atmosphere, they would only reduce global warming but not