Nice k.38 you got there. Looks like the finish on gun is original but a common way to spiff up your gun back then was to jewel the hammer and/or trigger. Looks like an owner did just that and had them plated then jewelled to spiff up the gun. You could possibly find an original hammer trigger set, have a gunsmith replace them for you. But if you just want to enjoy shooting the gun and not worried about selling it or the value - just leave it as is and shoot away. Very fun and accurate guns to shoot. Enjoy.