The Glass Painter of the Twelfth Century To understand the weight of medieval glasswork, one must look to the 12th century and the hand of Meister Gerlachus. He was not a painter of canvas, but a specialist in colored glass and black enamel painting. His work, specifically the Gerlachusscheiben, represents a precise intersection of religious devotion and technical mastery. Around 1170, he produced glass discs that utilized lead and col…