I own a very early/mid 1930, first variation Walther PP serial number 752,682 with appropriate design features including: C/N, split firing pin, heavy hammer without grove, deep safety well and fat safety, black cross-X supported grips, no chambered round indicator, etc. In addition the frame has a marking I am not certain of. The tang has a rectangular cut out on its upper surface to receive, or at least face, the rear action of the hammer. On the center flat surface of that tang well is an icon that vaguely resembles a crown consisting of three vertical, rabbit-ear shaped fronds on top of a ring. I do not believe I have seen other PP/PPK's with this marking and wonder if it is a factory inspector's mark, a local proof house mark, or a subcontractor's mark who might have initially supplied frames to Walther in 1929 as PP production was initiated. Has anyone seen a similar mark and, if so, on what years, serial numbers, and variations.