Cerekote finishes are tested with a salt solution. This is very much alike one of those glock torture tests you see on you-tube and facebook, but with a very specific and scientific metric applied. There are generally two ways to perform this test. Either the part is hung and put under a constant spray a saltwater, which most coatings will tolerate on the order of thousands of hours, or they are dropped into a vat of the salt solution and left to soak. Let’s face it, you don’t want to drop your custom glock in a salt bath, so these folks have done the testing for you. In this kind of full immersion test, the coating will hold up against rust for hundreds of hours. Try that with a blued slide, the difference in the results is obvious.