Forest glass (Waldglas in German) is medieval glass produced in northwestern and central Europe from approximately 1000–1700 AD using wood ash and sand as the main raw materials and made in factories known as glasshouses in forest areas.[1] It is characterized by a variety of greenish-yellow colors, the earlier products often being of crude design and poor quality, and was used mainly for everyday vessels and increasingly for ecclesiastical stained glass windows. Its composition and manufacture contrast sharply with Roman and pre-Roman glassmaking centered on the Mediterranean and contemporaneous Byzantine and Islamic glass making to the east.
- ^ Tait, H., 1991.