(S (S (NP (NP (BASENP (DT A) (JJ large) (NN number)) (PP (IN of) (NP (BASENP (NN bluestone)) (CC or) (BASENP (JJ spotted) (NNP Preseli) (NN dolerite) (NNS chips))))) (VP (VBN found) (PP (IN during) (BASENP (DT the) (NN excavation))))) (VP (VBD led) (S (BASENP (DT the) (NNS researchers)) (VP (TO to) (VP (VB conclude) (SBAR (S (BASENP (DT the) (NNS stones)) (VP (VBD were) (VP (VBN venerated) (PP (IN for) (BASENP (PRPD their) (NN healing) (NNS properties)))))))))))) (PERIOD .))