What is cased crystal
Cased crystal is identified as a glass piece that has two or more layers of different colors. The inner or outer layers of this glass can also be clear. You can view cased glass by peering inside a piece, such as a bowl or cup, and seeing a different color. In some instances, the outer layer of cased glass can be cut away in sections to bring out the color(s) of the previous casings beneath.
Cased glass is created in a couple of ways. One method involves blowing a new color inside of a piece that has already been created. Another process entails layering different colored glasses over each other. In each technique, the multiple layers of glasses are fused and blown out together to form the cased glass.