Art Glass Glass is often selected by Color. Using the left hand table select the box beside your desired color. The screen will display all art glass in that color range. Click on product image to compare art glass from multiple color categories. Glass is Often Selected by Transparency Values - Understanding Transparency Values can play an important roll for proper glass selection Transparency Values Explained - Understanding Transparency Values can play an important roll for proper glass selection Transparent - 100% Transparent glass, Visible light can easily pass through, do not contain any opaque glass or other light blocking material. Commonly referred to as Cathedral Glass. Translucent - Predominantly Transparent glass with some mixed in Opaque glass, allowing light to pass through in many or most areas. Semi-Translucent - Predominantly Opaque glass with some Translucent glass mixed in, allowing less visible light to pass through or pass through only in small areas. Opalescent - Glasses that are primarily or completely opaque, blocking direct visible light while retaining color when back lit.