Obsidian is not a mineral at all — it is volcanic glass, lava cooled too fast to crystallise. Fractured, it takes an edge finer than surgical steel, which is why it made the blades of several civilisations. That history follows it into the tradition: obsidian is the stone of cutting things away.
What obsidian is used for
It is called the mirror stone: the one for hard truths, for cutting cords to what is finished, for shadow work — the deliberate looking-at of what you'd rather not. The Aztecs scryed in polished obsidian mirrors. It is protective in the tradition, but bluntly so; people describe it as the stone with no bedside manner.
A sphere or flat piece if scrying interests you; a tumbled piece for the pocket. Buy it when something needs ending, is the traditional advice.
How to care for it
Cleanse with smoke; it holds heavy energy. Being glass it is water-safe but can chip on a hard edge. Cleanse with smoke — the tradition holds it accumulates what it cuts.
Obsidian in the shop
Stones that keep it company
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