A common term for the thick, circular center of a piece of crown glass, formed where the glass was attached to the punty during spinning. It features a prominent scar and distinct concentric ripples. Originally considered a low-quality byproduct of window glass manufacturing, these pieces are often used decoratively in doors and transoms.
Heard on the job
We need three more bullseye panes to finish the transom window above the main door.
Also heard as
- bullion
- crown