- Obsidian can produce cutting edges many times finer than even the best steel scalpels
- Some surgeons still use the blades in procedures today
In Neolithic times, trepanation -- or drilling a hole into the skull -- was thought to be a cure for everything from epilepsy to migraines.
It could even have been a form of emergency surgery for battle wounds.
But while there is still conjecture about the real reasons behind the mysterious procedure, what is known is that the implement often used to carry out the primitive surgery was made from one of the sharpest substances found in nature: obsidian.
Obsidian -- a type of volcanic glass -- can produce cutting edges many times finer than even the best steel scalpels.
At 30 angstroms
-- a unit of measurement equal to one hundred millionth of a centimeter -- an obsidian scalpel can rival diamond in the fineness of its edge.
When you consider that most household razor blades are 300 to 600 angstroms, obsidian can still cut it with the sharpest materials nanotechnology can produce.
Even today, a small number of surgeons are using an ancient technology to carry out fine incisions that they say heal with minimal scarring.
Dr. Lee Green, professor and chairman of the Department of Family Medicine at the University of Alberta, says he routinely uses obsidian blades.