Answer: Obsidian

If you think of anything at all when you think of obsidian, you likely think of school lessons long ago regarding prehistoric man. Millennia ago, long before the advent of metal working, early humans would carefully shape obsidian, a form of volcanic glass, into a sharp edge. This shaping process, called knapping, involved repeatedly tapping along the edge of the obsidian so that it cleaved along the natural structure of the glass. The resulting edge was incredibly sharp, so incredibly sharp in fact that it would be well into the modern era before it was replicated with any other material.

In fact, the edge of a carefully prepared obsidian blade is so fine that it measures a scant 30 angstroms across (an angstrom is one hundred millionth of a centimeter). By comparison, a modern razor blade, like the kind found in disposable shaving razors, has an edge width of anywhere from 300-600 angstroms. Even carefully prepared medical scalpels can’t compete with the smooth and fine edge of obsidian.

That’s exactly why custom scalpels made of obsidian have found favor among a small number of surgeons. Not only is an obsidian blade extremely sharp, but on a microscopic level, the edge of the blade is so smooth and fine that it can be seen cutting through individual cell walls like a razor sharp chef’s knife slides effortlessly through a tomato. The surgeons who use such blades for delicate operations swear by their efficacy and maintain that the extremely sharp edge leaves cleaner cuts that heal faster and cause less scarring.

While that may well be true, there are certainly barriers to the adoption of obsidian scalpels. Not only are they not FDA approved (a significant stepping stone for widespread adoption), but they require, well, a surgeon’s touch. Unlike steel blades, they are very delicate and cannot stand much lateral stress (lest the blade break and leave tiny fragments remaining in the patient).

Although obsidian scalpels are highly promising in terms of sharpness and speed of healing, it’s likely they will never be widely adopted but will, instead, be eclipsed by a more easily reproduced (and FDA-friendly) alternative made in a lab.