Charcoal fragment dates dolmen site to 4400BC
A TINY fragment of charcoal has led to a St Saviour’s dolmen being named as the oldest passage grave of its type on the Channel Islands.
The news came as a surprise to local experts, as the unusual structure on the Catioroc headland at the western end of Perelle Bay had been thought to be one of the more modern dolmens.
But a dig last summer saw a fragment of charcoal discovered, which gave a date of around 4400BC – making the grave more than 6,000 years old.
Last summer’s dig at Le Trepied was a collaboration between the States of Guernsey and the Clifton Antiquarian Club.
States archaeologist Dr Phil de Jersey said this was now the oldest reliably dated dolmen.
‘It is very important and it has pulled back the date a bit further than we expected,’ he said.
‘It implies that we were not too far behind what was happening on the French mainland at the same time. We were part of the first wave of these type of tombs, more than 6,000 years ago.’
Clifton Antiquarian Club vice-chairman Laurie Waite said when they started the dig they had hoped the grave was that old. As the dolmen is smaller than graves like Les Vardes, Mr Waite said there had been a perception that Le Trepied was more modern.
‘But maybe now we can turn that on its head,’ he said.
The oldest burial tomb of any kind in the Channel Islands is Les Fouaillages long mound, at Les Amarreurs, which has been dated to about 4900 BC.
But that is much smaller than the more commonly known dolmens and of a different design.
This was the early neolithic era, where islanders were using stone, flint and wooden tools, and were just starting to make stone axes.
It is believed that they first started settling about 5000BC, which could explain the start of the grave monuments.
Dr de Jersey said Les Fouaillages was a much smaller grave, with smaller stones, so would have been easier for a few people to build. But Le Trepied would have been a big project, requiring a team.
‘The middle stone at Le Trepied is about five tons,’ said Dr de Jersey.
He said that possibly the larger dolmen was a sign that the community was growing.
The speck of charcoal was found under the remnants of the mound that would have once covered the tomb and was dated to between 4400BC and 4300BC.
A second sample from the chamber entrance was from 3000–2900 BC, suggesting the tomb was used repeatedly over a long period.
Mr Waite said they believed the charcoal could have come from when the site was cleared to allow the grave to be built.
Two other Channel Island passage graves have previously been radiocarbon dated. Le Dehus in the Vale was dated to 4100BC from a human bone in the chamber.
A construction phase at La Hougue Bie on Jersey has also been dated to a similar period.
The club’s report on the grave should be published in the next two months.