NEWPORT'S medieval ship was at least as big as the Pinta - a ship used when Columbus discovered America, an expert suggests.

Historical expert Dr Ian Friel, curator of Chichester Museum, has been in correspondence with the Friends of the Newport Ship society to estimate the original size of wreckage found in the mud on the banks of the River Usk two years ago.

Dr Friel used a 16th-century measurement formula known as Baker's Rule to estimate the ship may have been between 375 and 478 tonnes in size.

That would put it on a par with Columbus' ship and larger than John Cabot's 'Matthew' on which he discovered Newfoundland in 1497. The figures, which were based on an estimated ship length of 29 metres and an eight-metre beam, have been welcomed by the Friends - although the voluntary society, which aims to one day restore the ship for a viewing public, has stressed the estimates are "just a ball-park figure".

"The problem you have with calculations such as these, is you are working based on a lot of estimations," said Friends' secretary Bob Trett, a former curator of Newport Museum.

"We still do not know the exact length of the keel until more timbers have been measured.

"There were also five or six different types of tonnes back then, so it is far from an exact science.

"It is fair to say though on what we have discovered so far, the Newport ship was pretty big.

"It was definitely at least 200 tonnes and when you think most ships in Newport would not have been more than 20 tonnes at the time, that gives you an idea of its size."

The ship's timbers are currently undergoing scientific tests led by Newport Museum to try to determine where it travelled and who might have used it.

In the meantime, the Friends are busy raising its profile, with an exhibition planned for this year's National Eisteddfod in Newport.