Hey,nice to be here! came across a Mauser the other day that has got me really puzzled. seral number is on the side rail, no manufacturer info. crest has been scrubbed, not enough left to i.d. it. the only mark that consistently appears is four diamonds, like the points of a compass. caliber is written "cal. 7.92" in script, rather than printed. The diamond stamp appears on the buttplate, receiver ring, and gas shield. Any clues would be helpful. TIA!