The Oman/Makkan hypothesis involves two sets of data: 1) a comprehensive archaeometrical program, and 2) a knowledge of protohistoric settlement in the Oman Peninsula. Twenty years of archaeological research have brought to light such communities, and substantial progress has occurred since the Sultanate of Oman initiated archaeological research on its territory. This article concerns research of archaeometrical results of a program on copper supply in the Middle East during the fourth and third millennia BC, and to examine what conclusions can be drawn from the interaction of foreign exchange with local communities.