Blue boulders have been seen on the surface of Mars in a vast crater believed to have been created by an asteroid.

Volcanic basalt stones with an azure tinge were photographed by the car-sized Perseverance rover as it explored the Jezero crater.

The 28-mile wide site is thought to have been formed after an asteroid impact 3.7 billion years ago and it has been explored for more than three years by Nasa’s Perseverance project.

The blue rock site, described as a “grab bag of geologic gifts”, has been dubbed “Mount Washburn” after a mountain in Yellowstone Park and amid the stones is another oddity, a white speckled rock.

“This was like the textbook definition of chasing the bright, shiny thing,” said Dr Stack Morgan, of Nasa’s Jet Propulsion Laboratory.

The rock, which is 18in wide and 14in high, was named Atoko Point by scientists.

It is a rock unlike anything else Perseverance has encountered in more than 1,162 Martian days.

It remains a mystery as to how the white rock in a blue boulder field was at the site but scientists speculate its mineral composition could have been created in an underground magma lake or it could have been moved to its current spot by flowing water billions of years ago.

“The diversity of textures and compositions at Mount Washburn was an exciting discovery for the team, as these rocks represent a grab bag of geologic gifts brought down from the crater rim and potentially beyond,” said Brad Garczynski, of Western Washington University in Bellingham, the co-leader of the current science campaign.

“But among all these different rocks, [Atoko Point] was one that really caught our attention.”