a cobble TP23 (161) displaying possible use as a stone hammer; a small rounded (greenstone) hammerstone which comfortably fits in the hand (U/S), a ‘pestle’ made of greenstone SF910 (518); a waterworn cobble SF932 (529); the fragment of a greenstone whetstone SF908 (515) with grooves and two long sharpening facets and the fragment of a saddle quern SF919 (518). Such variety is hard to explain and many comfortably date to a wide date range during prehistory spanning 3,000 or so years. Of particular interest is the greenstone pestle which was found embedded into the chamber pavement. Was this left as part of a votive offering during a visit to the monument over 5,000 years ago? The greenstone (an generic term for altered basic or ultrabasic igneous rocks) is likely to have been locally obtained. It was perhaps obtained from the Camborne area Group XVI which has been petrologically identified as a distinct and favoured source in prehistory. The exact extraction location is still unknown although it spans a catchment area 5km around Camborne.
Neolithic axes of Cornish greenstone have been found across the UK and into Ireland and so the value of objects made from Cornish greenstone were clearly highly valued and their discoveries in far flung parts of Britain show how widespread contact was between different communities during the entire Neolithic period. It therefore is of little surprise that a beautiful greenstone object such as the pestle was discovered at Carwynnen in 2012 so close to the source of the rock within the wider catchment of Carn Brea and Group XVI stone objects.