A modern quarryman squaring a block in a quarry on Marmara Adası (ancient Prokonnesos).
Quarrying activity on Marmara Adası (ancient Prokonnesos) began in the Classical period, if not earlier, and continued through the Byzantine and Ottoman period up to the present day. The peak period of quarrying on the island prior to the modern period was the Roman period, however. Prokonnesian marble is white with fine, sometimes thicker, grey veins.