The current research demonstrates the poorly studied question that is related to the inter-regional trade in mining raw materials in the Middle Ages in northern Russia. Mica ("Muscovite glass") was an important part of Muscovy trade with Europe. In the XV–XVIII centuries it was actively mined in North Karelia. There were large mines and towns where the local peasants worked. Published findings are from the excavations of mica of the XVII century church in Kandalaksha monastery. Chemical analyzes showed that the monks received mica with previously known deposits in the south of the Kola Peninsula. It extends the known historical region of production of mica in the Late Middle Ages and the territory of the Russian Lapland. This article is the beginning of work on the archaeological study of the medieval miners’ villages.