Wissmach Crystal/ Dark Red Transparent (color code 96-64) is a Prisma blend in COE 96 kiln glass, fiery amber and red streaks in a clear crystal carrier in a 3mm sheet, tested for fusing compatibility.
Appearance Unfired, the sheet reads as a sunset field of warm amber and orange, marbled with deeper streaks of true red running in loose horizontal currents, with fine seeds scattered throughout against the transparent ground. The first color in the name is the more dominant, so the clear crystal carries the blend with the red streaking through it, and the streaking is unique to each sheet, so no two are identical.
Striking This blend may strike to a deeper, denser color in the kiln, as Wissmach notes for its Opaque and Prisma lines, and Dark Red in particular tends to come out of a firing noticeably richer than the amber leaning sheet in your hand. Fire a sample chip first if the exact shade matters.
Working notes Wissmach’s recommended full fuse schedule for a 6mm project made from two 3mm layers: heat at 300 degrees F per hour to 1225 F and hold 30 minutes, then 600 per hour to 1460 F with a 10 minute hold, cool as fast as the kiln allows to 960 F and hold 1 hour, then 100 per hour down to 700 F. These numbers come from Wissmach’s current published firing guidance. They are guidelines, not guarantees. Kilns differ, so fire a small test piece first.
Reactions Dark Red is a sulfur bearing color on Wissmach's COE 96 chart. Fired in direct contact with copper bearing colors such as Reactive Blue, Deep Sky Blue, Turquoise Green or Sea Blue, it can form a darker reaction line where the glasses meet. Results vary by batch and firing, so run a small test tile before committing the pairing.
Format and sizes Sold as a 3mm sheet in 8" x 10.5", 10.5" x 16" and 16" x 21" sizes. Choose your size from the options on this page.
Fusing and compatibility Tested compatible with other Wissmach COE 96 kiln glass. With glass from other makers, a matching COE number alone does not guarantee compatibility, so fire a test tile before committing a project.
More of this color Also available with a Luminescent coating .
Helpful downloads Wissmach COE 96 Kiln Glass Catalog
Technical data courtesy of the Paul Wissmach Glass Co.
Description updated: August 13, 2026
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