Another bluestone mystery

A few years ago I was hunting for "bluestone" regferences, when I came across an ancient reference (from John Leland) to abundant blue stones being used in early buildings at South Cadbury (or Arthur's Camelot, if you prefer). This is an Iron Age hillfort, used again later on in the Dark Ages. Could "bluestones" from Preseli or elsewhere have been used in the construction of the original hillfort? Or was the blue stone more local? It seems most likely that the latter was the case. I got these helpful replies to my enquiries:

1. "I think that the "dusky blue stone" referred to by Leland must be the local Blue Lias. There aren't any igneous rocks in that area that might have been used as building stone. You can find some information in the excavation report if you are able to get hold of a copy: "John C Barrett, P W M Freeman and Ann Woodward 2000, Cadbury Castle, Somerset: The later prehistoric and early historic archaeology, English Heritage Arch Report 20". There is a map of the local geology on page 9, which shows where the Lias outcrops and also a little about building stone on page 267. I hope that this might, belatedly, be helpful". With best wishes, Fiona Roe.

2. "You are probably right in interpreting Leland's rather vague comments as referring to Lias. There is an outcrop to the west of the hillfort and it was used as building material from the Roman period onward - mainly by them for roof tiles as it breaks in a flat plane. The walls that Leland saw would have been the Late Saxon refortifications that you can still see eroding out of the inner bank, they are mostly the local yellow sandy limestone, but reused other stuff that was lying about. Excavations around the hill have over the last few years turned up burnt stone that goes a bright blue or red colour, and in some cases seems to have been selected for particular purposes based on colour". Hope that helps, Clare Randall.

Olwen Williams-Thorpe once looked for foreign stones around South Cadbury, but discovered none that she could be certain about. Rob Ixer also reminded me that there are some local basalts not far away -- not sure what colour they are.......