Amethyst | Colored

Manufacturers added manganese oxide to "mask" the natural green or aqua tint caused by iron impurities in the sand used for glassmaking.

When exposed to sunlight (UV radiation), the manganese undergoes a chemical change, shifting the glass from clear to various shades of amethyst or violet. 2. Archaeological Significance Colored Amethyst

SCA glass is a critical diagnostic tool for cultural resource assessments and archaeological surveys. Manufacturers added manganese oxide to "mask" the natural