My New used rifle has a frizzen that is “in the white” I would like to brown it so it matches the rest of the rifle. Can this be done cold or does it need to be done hot? If I do it hot, do I need to be concerned about the hardening of the frizzen in a way that would be to the detriment of the life or spark of the frizzen. Never did any blueing or browning browning before so recommendations for temperatures, techniques and products would be most appreciated. Thank you experienced firearms builders!