Various carvings of knives and axes, the usual lattice and ring-and-cup designs have been known to exist on several of the stones at Stonehenge since the early 1950s. But recently Wessex Archaeology archaeologists used a high-end Minolta scanner to scan one of the uprights. Their scans, enhanced, appear to reveal two axe heads, of the sort seen on stones in Scotland. I can’t see it myself, but you can read about it in the November issue of British Archaeology or on this site.
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