Cannonball found in excavation work at Whanganui's Sarjeant Gallery

The cannonball was found just after 3pm on Wednesday. Photo / Bevan Conley

A cannonball found during the excavation of the Sarjeant Gallery's extension has been taken to Wellington for testing.

It was found around 3pm on Wednesday, with work immediately suspended at the gallery's extension at Pukenamu Queen's Park and an explosives expert called in.

Mayor Hamish McDouall told the Chronicle the cannonball went to Wellington this morning.

"It will have an x-ray there and determine whether it is a cannonball with an explosive charge. Potentially, if it's hollow, it's likely to have some sort of explosive charge.

"If it's solid, then obviously it is just a projectile."

McDouall said he had studied cannonballs extensively since the discovery.

"I can tell you about all different kinds of cannonballs.

"It's an important historic find, of course. But we shouldn't ignore the fact that Rutland Stockade and the cannonballs from there were often used against the local tangata whenua. So we should regard it with a bit of sobriety as well."

McDouall hopes to have an exhibition of all the items found during the gallery's excavation.

"If we don't have to explode it, we will keep it. I think that's part of the treasure trove that has been discovered there."

McDouall said toy cars and marbles have also been found on the site, the grounds of a former school.

"It's quite an incredible find, everything is an incredible find. We will certainly be keeping it all and hopefully one day exhibiting it. I think that would be a remarkable exhibition."

He said there are likely to be household items found in the area, known as "the rookery" for many years.

"Up the top there for some years there was a bit of a squat, where a lot of settlers who weren't wealthy enough built raupō huts.

"Then of course that whole area had Māori settlement there as well because of its position as a strategic place.

"There are clear protocols around finding things and it may not be the last cannonball."

Work has resumed today on the site.