An undiscovered ring cairn near Gernos Fach?

A friend who frequently wanders in the wilderness in these parts has drawn my attention to an unrecorded feature not far from Gernos Fach, on the flank of Banc Du  --  grid ref SN 077 345.  We can see it faintly on the satellite image above, not far from a little pond.

She says that just now the feature is even more prominent to the naked eye, even from ground level.

If you look carefully you can see a faint change in the vegetation, bringing out a distinct circle of green in an area dominated by moorland vegetation.  It's to the SE of the pond, right in the centre of the photo.  There are lots of modern tracks criss-crossing this area, but this "feature" looks rather different from anything else on this moorland.  So -- might it be a ring cairn like the others on Carningli and Dinas Mountain?

Note that this is less than one km from the Waun Mawn standing stones which were investigated by MPP's team a couple of years ago, in the hope that there might be some remains of a gigantic stone circle there.  I gather that particular hypothesis has gone by the board, since the stones which still remain standing and fallen cannot be fitted onto the circumference of any circle, large or small........

But thinking of man-made features, the summit of Cnwc yr Hydd (just to the north of the main standing stones) is rather interesting, since it is distinguished by a string of small quarries (at least twenty pits) which I find rather mysterious.  They don't seem to be places where large stones can have been quarried, since as far as we can see the bedrock is friable shale and mudstone, partly metamorphosed -- the altered sediments that exist right across this area between the exposures of dolerite and rhyolite belonging to the Fishguard Volcanic series.  More investigations are needed...... there is a chance that the quarries are modern, having been used for roadstone for the Gernos Fach farm track. Click to enlarge the image.