From Green to Purple

from Rande Bly of Birmingham, AL

John Styler had asked a question a couple of weeks ago I wanted to answer. He asked about any Steuben that may have contained manganese and had the potential to turn purple from direct sunlight. My research led me to the discovery of this Steuben color. That color is called Window Glass Green, also called Pale Green. Manganese was used in this color to remove some of the natural green tint in the glass caused by the natural iron content in the silica sand. Glass companies did the same thing with glass for windows to remove the green tint and make the windows more clear. Years later the windows turned purple and they increased in value. Do not allow your pieces of Steuben Window Glass Green to be exposed to direct sunlight because they will be dramatically reduced in value. Carder had a formula called Pale Nile Green that contained a mere 22 ounces of manganese per 1000 pounds of glass. It was the sole colorant in the mixture.

Steuben Window Glass Green is black light reactive as is all glass containing manganese. The reaction is nothing like glass containing uranium but rather a soft pale green glow familiar to many experienced glass appraisers.

Window Glass Green is very rare. It is more rare than Moonlight and deserves the best of care so keep it out of direct sunlight.