Throughout history, many different objects have been used to facilitate trade for goods and to measure wealth. Today, we usually think of dollars and coins when we define what we regard as money, although much commerce is carried out without any physical currency at all. Value is counted by entries in bank and credit card accounts, and the transfer of money often takes place through electronic impulses between computers. Objects have served the same purposes as well, in other times and places.

Throughout Africa's past, many objects have served as money - salt, shells, beads, metal, indigenous coins, European coins, jewelry, woven cloth, weapons and tools. The keys to understanding why a particular object came to be used as currency are acceptability and value. Acceptability encompasses such aspects as familiarity, usefulness and artistic expression, which add to the intrinsic value of the medium itself. Thus, while the scarcity of copper might have caused it to be exchanged on that basis alone, its use was further validated through the forms into which it was cast. Iron was more ubiquitous in African societies, but refining, forging, forming and decorating similarly increased its value.

Economists and financial historians writing about mediums of exchange typically define currency as a durable, divisible and accepted means of measuring and storing value. Governments and laws largely define acceptance today, but over the course of history, acceptance was more often conferred by broader cultural currents, including religion, myth and beliefs about the nature of the universe. In Africa, where few extensive nation-states existed, the needs of trade and commerce depended on commonly held beliefs or values that spanned great geographical distances and an almost unimaginable diversity of activities. Consequently, the currency needed for even the simplest daily transactions was backed by shared beliefs as much as by the intrinsic value of the currency itself. Transactions that involved significant life events-marriage, procreation, health and death-were validated by objects with high intrinsic, symbolic and artistic values.

This exhibition is a celebration of the art of the currencies used in Africa. It also explores the beliefs that supported the monetary systems of African societies and led to the elaboration and transformation of plain currencies into objects of beauty.

To provide a context for these currencies, this exhibition includes a selection of objects commonly used as mediums of exchange, such as cowrie shells, beads and bundled and woven textiles. The metal currencies, which are the focus of this exhibit, range from conventional forms to highly valued complex designs executed with considerable technical skill and artistic sensibility in rare and precious metals.

COWRIE SHELLS

These shells were an ancient money used not just in Africa, but throughout the world, predating the use of coins or in some instances used in the same economy as metal coins. Imported from the Maldive Islands in the Indian Ocean, these polished, olive-sized shells served for small everyday transactions and, gathered together in the millions, for bridewealth (a groom's gift to the family of the bride) and other major purchases and gifts. In the 18th century, one could purchase a cow for 2,500 shells, a goat for 500 shells and a chicken for 25 shells. The shells were counted and measured in many different combinations, but the most typical in some parts of Africa was the rotl, a string consisting of 32 shells, which was then aggregated in strings of 5 to constitute a bunch. Ten bunches was called a head. The shells were believed to possess the power of fertility, thus ensuring their acceptance throughout the wide territories of Africa.

CLOTH STRIPES AND RAFFIA MATS

Another widely used common currency was woven goods. Two types are a part of this exhibition-the cotton woven strip roll and the raffia mat or bundles. Strip cloth known among Nigerians as gabanga was often plain and undyed. As a rule, the strips had a standard width between four and six inches.

Variations in width and the quality of the weave gave the parties of the transaction a means to negotiate value. Cloth was also frequently used in connection with other currencies, such as brass rods, lending additional flexibility to the negotiations. As there was no government regulation of cloth production, its circulation was limited by the cost and effort of production (the need to spin fibers into threads and then weave the fabric) and by demand. Cloths or mats of more-or-less uniform size were used for gifts, peace offerings, payment from a son to his father upon attaining adulthood and payment upon the birth of a child or the burial of a parent. Cloth currency was also used as a tribute for a spouse who remained chaste or, by contrast, as a penalty for adultery.