I spent two weeks last January in a workshop outside Teotihuacan, watching a man named Don Refugio reduce a fist-sized chunk of volcanic glass into a blade thin enough to split a hair lengthwise. Forty-seven years at the craft had given his hands the unhurried certainty of someone who understood that obsidian does not forgive impatience.
The Edge That Outlasts Steel
Obsidian fractures along conchoidal curves, producing an edge measured at three nanometres — several hundred times sharper than the finest surgical steel. Electron microscopy confirmed this in 1984. The finding has not been surpassed, because the material itself has not changed in forty million years.
The mirror does not flatter. It shows exactly what stands before it, unvarnished and inverted — which is perhaps why the Aztecs assigned it to the god of change rather than the god of beauty.