Black Obsidian (Metastable).
Origin: Mexico
Size: approx. 3–5 cm
PRICE PER KG
This specimen of black obsidian features a fascinating layer of surface alteration, caused by the release of metastable minerals that create an exceptional colour contrast with its glassy core. This process, driven mainly by the formation of alteration aluminosilicates, creates an outer patina that enhances the depth of the black obsidian interior. The specimen is a unique geological testament to how chemical interaction transforms volcanic glass, making it a highly valuable object for mineralogical collecting and petrological studies. Its dual aesthetic stands out not only for its rarity, but also for the intrinsic beauty of natural weathering processes.
