Asante traders kept internal weights, used European standards for coastal trade

Gold dust functioned as the primary currency across the Asante Empire's trade networks from around the 15th century onward, valuable enough that accurate, trusted weighing was central to every transaction. Asante merchants inherited an Islamic mithqal-based weighing standard from Dyula traders active in trans-Saharan trade from the late 14th century, and Akan goldsmiths developed their own brass weights, known as mrammuo (plural abrammuo), calibrated to that standard for measuring gold dust in transactions among themselves.

When European traders arrived on the coast, they operated under entirely different weight conventions, and simply forcing every Akan-to-Akan transaction onto a foreign standard would have surrendered a system Asante merchants and goldsmiths fully controlled and could verify against their own accumulated craft knowledge. At the same time, refusing to accommodate European weight conventions at all would have made coastal trade with Europeans needlessly difficult.

Kept their own abrammuo weights for internal Akan trade, but used European standards for coastal deals, matching the standard to the counterparty.

Internal trade stayed auditable and verifiable within a system the Asante fully controlled.

Switching standards only for European transactions kept external interoperability without diluting internal integrity.

Context-sensitive standards let the system serve internal control and external trade simultaneously for centuries.

When dealing with both an in-group and outsiders, keep your own standard for internal dealings and adopt theirs only for external ones, rather than forcing one universal standard.

The arrangement let internal Akan gold-dust trade stay legible and auditable within a system the Akan themselves fully understood and controlled, while still allowing functional, interoperable trade with European merchants operating under a different convention, over several centuries of active use from roughly the 15th to late 19th century.