Quote Originally Posted by Tom1956 View Post
I didn't really intend to "boil" it. My idea was to make a double boiler out of 2 cookpots, and not let the inner one actually come to a boil. I'm afraid of removing the coating no matter what I do, but particularly that.
The double boiler is probably a good idea, you can still raise it to whatever temperature water boils at your altitude without the agitation risking chipping it. You won't remove the coating in boiling water. Some (many modern) coatings are more durable than the glass they are applied to.