The provenance of the gold of the Byzantine Empire is still considered a difficult archaeological issue in its investigation. One of the regions that probably contributed to the creation of the store of state gold is Macedonia and its rich deposits. Mining of gold was held in parallel with mining and manufacturing of iron in some metallurgic centers, such as Aghistro and Makrychori, between the thirteenth and sixteenth century AD. The study of the remnants of metallurgy from four relevant locations suggests that two of them showed a small-scale activity, whereas the other two had a large-scale production. The technological complexity of the Byzantine world is evaluated through the thorough research on the overall organization of the production process, which aimed at the better exploitation of raw materials.