One of the flanking pillars shows a dozen cup marks, perhaps carved during ceremonial rites. The recumbent stone has been broken in two pieces, perhaps by the action of frost.
An investigation by archaeologists has found cremated remains at the base of the upright stones. The cremations seem to have been performed at the same time the circle was built.
Sometime later the interior of the circle was burned, then filled with a cairn of stones with a kerb of small boulders. More cremated remains were found under the cairn.
Near the stone circle and cairn is a small earthwork enclosure, constructed around 1500 BC. This enclosure seems to have used as a form of burial ground, with cremated remains of over 30 people discovered, and it remained in use until well into the Bronze Age, around 500 BC. Of the 32 total remains found, 8 were children, between the ages of 3 and 6. The ashes of some people were placed in urns, others were laid out in graves. One particular human remain stands out; it was a partially cremated body of a man, holding a stone pendant.
Loanhead is simply a superb site. The combination of the stone circle with its huge recumbent stone and the cremation cemetery make this a must-see if you are interested in ancient sites. Another impressive recumbent circle is at Easter Aquhorthies, also near Inverurie.