It's Cerakote. The primary consumer application for it is coloring firearms. I opted for it after seeing the road bike the builder built for himself and got coated. The color (Robin's Egg Blue) is now an official Cerakote color you can buy. Mine is a custom mix of Zombie Green and gloss white. Mixing their colors with gloss white creates a pearl finish. Enve allows it without voiding the warranty as long as you don't bake it at too high a temperature. IIRC, it was only a few hundred dollars.

www.paintbytodd.com did my application.