Has anyone tried case coloring?

I see people torching, which gives a kinda-sorta similar effect, but has anyone tried old-school case coloring like used to be done on antique high quality firearms?

I have a gunsmithing book from the 1800s that gives good instructions on how to do it, but I need bone meal, iron pipe big enough to hold the parts, a bellows and an open fire.

I'm talking about achieving a look sort of like this, every one has a different look. Apparently the higher the polish prior to case coloring, the better the pattern & colors:

This isn't the nicest I've seen, just a pic grabbed off the web, there are tons of colors in person & some of the old timers were even able to control or create intentional patterns. (Not sure how that was done.)

It is done with carbon steel, I don't know if it would work on stainless.

No, it won't work for stainless. Case coloring can be done with a make shift enclosed forge too. (made from fire bricks)

Case coloring only works with carbon steel. It takes a hell of a craftsman to get the look like above. Tried my hand at it before. It's an art.

I will not work on 'stainless'; it is a process of en-casing the part to be 'casehardened', in an enclosure, many times a steel pipe, being packed with old leather, and heated to cherry-red, and allowed to cool. Carbon is randomly imparted to the surface, resulting in the coloring you require. And, I might add, a VERY wear resistant surface.