Case hardening is not decorative -- correct. And color case hardening is not primarily decorative, either, it's just the effect/result of uneven heat in the case hardening process. For those who find the appearance attractive, it may be thought of as decorative, but that's not the reason it's done.T. O'Heir said:Case hardening isn't decorative. Case hardened colouring is though. Goes on just like cold bluing. Comes from these guys.
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Color case hardened parts don't hold their colors well. Many manufacturers of CCH guns lacquered their frames to make it hold up better.
The HARDENING doesn't wear, but the colors don't wear well.