Loch of Skaill Niche

Leaving Skara Brae this is along from the second passing place by the Loch of Skaill. Had to remove a veil of grass to ascertain it really was the thing I had previously found. To the right of it a stone is marked with that official bear’s-paw ‘sunburst’ symbol, look for that. Still not 100% certain it is not geological or adapted natural still. IIRC it faces across to a very small unmapped ‘islet’ in the loch. Stone ‘block’; straight 0.7m then ‘niche’0.8m across and then it goes behind at an angle. Enclosing sides 0.5m and 0.7m long and 0.35m high, slab above 0.2m deep.