Wissmach White/ Deep Sky Blue (color code 96-21) is a Prisma blend in COE 96 kiln glass, milky sky blue and white streaks in a 3mm sheet, tested for fusing compatibility. Wissmach's own name for this blend is Peacock Feather Tr/White.
Appearance A milky peacock blue fills the sheet, with soft white wisps drifting through it in loose horizontal currents rather than hard stripes. Prisma is Wissmach's blend of two or three colors in one sheet, and the first color in the name leads, so under Wissmach's naming the peacock blue is the dominant color here with white feathering through it. The streaking is unique to each sheet, so no two are identical.
Striking Wissmach notes that its Opaque and Prisma colors may strike to a deeper or denser color after firing, so plan on the fired sheet reading a little richer than the unfired one. Fire a sample chip 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 This blend carries the copper marker on Wissmach's COE 96 chart. Fired in direct contact with a sulfur bearing color such as String of Pearls, Oyster Pearl, Gold Tone or Honey, it can form a darker reaction line where the two glasses touch. Results vary by batch and firing, so test the pairing first, whether you want the line or want to avoid it.
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.
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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