 The kerb @-@ stones around the tomb display some <unk> ; those on the northern side are mostly rectilinear , while those on the southern side are smaller and largely irregular in shape . It is probable that there was an ancillary dry @-@ stone wall constructed using blocks of <unk> from the geological <unk> beds , as is evident at Chestnuts Long Barrow . Given that such blocks of stone rarely occur naturally , it may have been <unk> . 
