Abstract
The cobalt mine of Qamsar, south-west of the city of Kashan in central Iran, has long been considered a prime source of cobalt ore from ancient times until the early twentieth century AD. A review of the known Persian and European historical accounts describing the deposit, its cobalt ores, and the technologies involved in the production of the blue pigment is presented here. The aim is to provide a comprehensive background against which to understand the traditional ore processing technologies involved in the production of the famous cobalt blue pigment.