Page 9: Cross Sections of Medieval Glass

"Flight to Egypt"

Looking at cross sections of medieval glass produced from the 12^th through the 14^th century, the striated red layer takes up about half of the body of the glass. Flashed red glass from later periods exhibits the red as only a very thin top layer similar to the flashed red being produced today. Modern flashed red lacks the striations found in the medieval period.

Fragments of Medieval Red - Glencairn Museum