I have an original Leman in .36 cal. The octagon barrel is browned with a copper blade front sight. The percussion lock and double set trigger are browned. All other furniture, ie...muzzle cap, ram rod pipes, trigger guard, cap box and butt plate are brass. I might add, the barrel has a good bit of wriggle engraving on the top flat in addition to the signature.
One odd feature is that the single lock bolt is brass. Of course, that may have been replaced at some time in the past.