Puzzle

The old church graveyard in our town is rarely unlocked, and when it is, it's a certainty I won't have proper camera with me. Hence this phone shot of a nice, deeply carved little stone.  which is a bit of a puzzle. The carvings are presumably trade tools, but it's not obvious to me which trade. The upper device  looks like a slater's  hammer but the lower is a bit like a sextant ( mariner) and a bit like a compass (mason), but not quite like either. One reference book says that 'very rarely, a coalmaster's compass is shown'. It would be nice if I had found a 'very rarely'.

Edit to add: I found an image of a collier's compass, and this nothing like it.