1.2" Colorful Sieber “Agate” Copper Slag - Copper Smelting Byproduct

This is a 1.2" wide specimen of colorful Sieber "agate". Sieber agate is actually not agate at all, but instead a byproduct of ancient copper smelting from approximately 1,400 years ago. It is a glassy copper slag that is technically a synthetic from of obsidian. It comes from the Oberhütte slag locality in Saxony-Anhalt, Germany.

It comes with an acrylic display case.