Spectrum Classics includes Spectrum Wispies, Semi Translucents and Translucents.
Wispy Opalescents are traditionally composed of about 3/4 cathedral glass color and about 1/4 opaque white glass. The white opal is hand-ladled into a moving stream of cathedral color. The two glasses are then stirred together, by hand, just before the sheet is formed. In the finished sheet, wisps of opal display as both surface variegation and internal shadowing, generating reflection and depth.
Semi-Translucent Opalescent mixes are primarily opal glass, eliminating the perception of images through the sheet. Because of their relative opacity, these glasses are highly reflective in nature. With backlighting, natural or artificial, they reveal a captivating, luminescent glow.
Translucent Opal mixes are about 50-50 cathedral color and white opal glass. The larger proportion of opaque white reduces light transmission and increases surface reflection. Some translucents involve multiple cathedral colors with white, and others use colored opals to achieve their individual character.