After reading this I made a visit to Pikestones to check if there was any further damage, there is even more pummeling of the spiral, the top of which is now almost obliterated, done with a a stone which is currently thrown inside the chamber, the damage so far is to the top of the spiral but it wouldn’t surprise me if the bottom part is next.

The spiral dates to late October/ Early November 1993, I was up there in October there was no spiral, I went back in November with a camera, the spiral had appeared.