Stiff Black Opalescent - Bullseye (COE 90)
• Approximate Diameter: 4-6mm
• Approximate Length: 14"-16"
• COE: 90 Compatible
True black, looks identical to Black Opalescent.
Torch: Holds a crisp edge in the flame longer & hotter than Black Opalescent.
Kiln: Stable. No color shift. Compared to Black Opalescent, Stiff Black has a slightly higher viscosity, meaning that it is a stiffer glass. In most kilnforming applications, Black and Stiff Black can be used interchangeably. Kilnforming applications where differences between Black & Stiff Black might be noticed include working with elevated drop ring molds and kilncasting.
Rods are pulled from re-melted Bullseye Compatible sheet glass. Rod is sold in lengths of approximately 18in. (450 mm) and 4-6mm in diameter. Bullseye rods are graded either as F (recommended for both kilnwork and torchwork) or T (recommended for torchwork only).