Hello Bob
I saw it during a visit a few years ago, and found that Burl had written about it being the surrounding quartz stones of a cairn. We have two pictures (poss more, I only looked for my own!) on this site page - here's a link to one:
http://www.megalithic.co.uk/modules.php?op=modload&name=a312&file=index&do=showpic&pid=22140
and the other photo is below it.
You need to scroll down to the last photo showing on the site page, then click on the link to 'more photos' (than the 25 showing), and you will see the total collection posted here.
I'd actually dowsed a route from the main circle which passed near this one on the way to what I think is a destroyed cairn in the level ground below there.
(PS: When the link to that photo is open, you could click on the links above it, ie: 'next photo', then 'previous photo' to see a view of the 2nd 'circle' from above, and the 'destroyed cairn' or 'tomb' I just mentioned.)
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