Engravers uses a high speed air turbine grinder capable of speeds up to 85,000 rpm. A wide assortment of "burs" are used to carve out the metal. Each bur has it's own purpose and help to create the illusion of 3 dimensions on a flat surface.
It's roots dating back thousands of years, hand sculpted brass dies gives you what is still considered the "Cadillac" of printing.