Although coins are the most familiar form of money, other objects have also been widely used and accepted as payment in commercial transactions over the centuries and on different continents.
Shells are one of the most widespread forms of traditional money in the world. Cowrie shells were common currency in Africa and Asia until the 19th century. They also had symbolic and ceremonial value related to the concepts of wealth, happiness and fertility. Additionally, they were used on objects of great ritual significance, such as clay masks of human faces encrusted with these shells.
Tukula, another exotic type of money, was used in Central Africa from the 17th century until quite recently. It consisted of a long, roughly rectangular block made of wood pulp and engraved with geometric designs once the block had hardened.
Plant products have also been used as a method of payment in many places. In China, tea bricks were used as money until recent times. These blocks of compressed tea leaves had chequerboard marks on the back, which could be used to divide the brick into smaller quadrangular pieces of lesser value for paying small amounts.
Metal has been turned into many objects used as currency. The most obvious example is our modern-day coins, but there are more curious cases, such as the copper tajaderas or Aztec hoes used by 16th-century Mexican indigenous communities in trade transactions. Today we continue to use non-metallic currency such as plastic credit cards, our electronic money.