What is Slag Glass? A Discarded History

Aug 28, 2020
Issue 3442

Alan – This article about slag glass may be of interest to some members who enjoy knowing about various techniques/chemistry related to glassmaking.

Audrey Lipton

Slag glass gets its name from slag, or the byproduct of steel production. When iron ore is smelted in that process, the remaining residue is a glass-like, often glossy material that takes on different colors depending on the minerals and elements present in the iron. The visual marbling of this slag is reminiscent of slag glass, however, the presence of actual slag in slag glass pieces depends on how it was created.

Symposium 2025
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