Volcanic glass, 70 million years cold

Obsidian, cut and polished

$46

Obsidian is not a mineral. It is glass — lava that cooled too fast for crystals to form, which is why it fractures into curves instead of breaking along flat planes. This piece is cut and polished to a flat face; the edges are chamfered so it can be handled without gloves.

Material

Obsidian (volcanic glass), cut and polished

Hardness

5–5.5 on the Mohs scale

Form

Cut slab, chamfered edges

Care

Wipe with a soft cloth. Edges are chamfered but still sharp — handle as you would a glass offcut.

Treatment

None declared — written confirmation from the supplier is still being collected

Every stone carries a treatment line in its specification table. "None declared" means the supplier has not told us of any treatment and we are still collecting that statement in writing. If a stone has been heated, irradiated, dyed or resin-filled, we say which — a treated stone is not a defect, but it is a different object, and some treatments change how it should be kept.

Ships from Hangzhou in 2–5 business days. Delivery is typically 7–15 business days to the US and 8–16 to the EU, UK, Australia and New Zealand, customs permitting. Import duties and taxes are charged by your country's customs, not by us, and are payable on delivery. The United States ended its $800 duty-free exemption on 29 August 2025, so US orders now attract duty at every value. The EU introduces a flat €3 duty per item on goods below €150 from 1 July 2026. Shipping details.