Wissmach Reactive Blue/ Black (color code 96-38) is a Prisma blend in COE 96 kiln glass, azure blue shaded with smoky black in a 3mm sheet, tested for fusing compatibility.
Appearance A medium azure blue with a smoky gray veil drifting across part of the sheet where the black component thins through the color, more weather than stripes. A few fine seeds ride in the glass. Reactive Blue is the first color in the name and the more dominant, and the streaking is unique to each sheet, so no two are identical.
Striking Like Wissmach's other Opaque and Prisma colors, this blend may strike to a deeper or denser color in the kiln, so expect the fired result a touch richer than the unfired sheet. Run a small 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 Reactive Blue brings copper to this blend on Wissmach's COE 96 chart. Fired in direct contact with a sulfur bearing color such as String of Pearls, Gold Tone, Yellow or the red and orange family, it can form a darker copper sulfide line where the glasses meet. Run a small test tile first if the effect matters to your design.
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
Spot an error or have feedback on this description? Report it here .
