This glass is primarily transparent blue green with an irridescent sheen speckled with silver. Nebula grows silver crystals once encased with a thin layer of clear, forming blue-green swirls inside. Repeated reheating of the bead enhances this effect. If reduced it takes on a chrome-like shine. It looks great encased with a tint color, and is particularly attractive underneath Effetre dark lavender 081. In some applications, the color looks like a photo of outer space, thus the cosmic name.