Photo: the rock art was found somewhere near to the Scottish border, but the location has been kept secret for security reasons. Courtesy of Dr Aron Mazel.

Archaeologists have been left baffled by a series of mysterious rock carvings discovered in the North East of England.

The unusual markings were spotted by a farm hand who alerted a group of field researchers from the University of Newcastle. The team were in the area to work on a project examining prehistoric "cup and ring" rock art in Northumberland.

However, Research Associate with the School of Historical Studies at the University, Dr Aron Mazel has so far been totally stumped by them.

"We have absolutely no idea what they are, as they are nothing like anything we or anybody else we have talked to have seen before," said Dr Mazel.

Photo: according to experts the unusual concave markings have never been reported before. Courtesy of Dr Aron Mazel.

The carvings were found hewn into one, isolated sandstone boulder near Wooler in north Northumberland, close to the Scottish border.

In an area well known for its rock carvings, it is not unusual for people to make new discoveries. But these are nothing like the "cup and ring" style markings more commonly associated with prehistoric rock art.

As well as a group of concave spherical shapes around 20 cm in diameter, the carvings include a shape resembling an adult footprint, several deep scores and another shaped like a heart.

Dr Mazel has been investigating the markings alongside Stan Beckensall, an international authority on rock art. But despite 60 years of experience between them they have so far been unable to identify what they are.

Photo: Dr Aron Mazel (left) and Stan Beckensall are rock art experts, but have appealed for help in identifying these newly discovered carvings. Courtesy of Dr Aron Mazel.

Furthermore, experts from English Heritage and the Royal Commission on the Ancient and Historical Monuments of Scotland are equally confused.

"There have been people living in the Northumberland area since the start of the Mesolithic period around 10,000 years ago," said Dr Mazel, "but I would think that these markings were made after cups and rings, probably during the last 3000 years. But until we know more about these markings it would be hard to pinpoint which era they belong to."

So, as Stan Beckensall explained, the pair are appealling for anyone who has any information that could help identify the carvings to come forward.

"As far as I know, these markings are unique and nothing like them exists anywhere in Northumberland or in the British Isles," said Stan.

Photo: the North East is well-known for its high density of rock art, but these new styles of markings have never been reported before. Courtesy of Dr Aron Mazel.

"That’s why we are keen to draw people’s attention to them – seeing the pictures of the markings may prompt somebody to come forward with new information, perhaps relating to rock art samples they have viewed elsewhere."

One discounted suggestion was that the carvings were created by the rock having been used to sharpen metal.

Another possibility put forward is that they could be linked to the early medieval monks and hermits who lived around the sandstone escarpments of the area.

"It’s important that we find out what these markings are as any information could shed light on the prehistory and history of northern Northumberland." added Dr Mazel. "We’d also be able to tell people a bit more about their ancestors who lived here many years before them."