Well that is one thing smith has over glock, their slides are nitrided stainless.Factory Glock slides are carbon steel, not stainless steel. I don’t remember the exact composition of the steel.
Since 2011, Glock has used Melonite as the metal treatment for the slide. Before that they used Tenifer. The two finishes are very similar, but the EPA likes the chemicals used in Melonite a lot more than they liked the ones used in Tenifer.
Melonite is a proprietary nitride process licensed by Kolene.