Mars meteorite 'Black Beauty' is in a class of its own

           The rock was picked up in 2011

A dark lump of rock found in the Moroccan desert in 2011 is a new type of Martian meteorite, say scientists.

Weighing 320g, the stone has been given the formal name Northwest Africa (NWA) 7034 - but is nicknamed "Black Beauty".

Its texture and chemistry set it apart from all previous objects picked up off the surface of Earth but known to originate on the Red Planet.

The researchers' analysis, reported in Science magazine, shows the meteorite to be just over two billion years old.

The study was led by Carl Agee from the University of New Mexico, US.

"It has some resemblance to the other Martian meteorites but it's also distinctly different in other respects," he told BBC News, "both in the way it just looks in hand sample, but also in its elemental composition."

There are just over 100 Martian meteorites currently in collections worldwide. They were all blasted off the Red Planet by some asteroid or cometary impact, and then spent millions of years travelling through space before falling to Earth.

Their discovery was mostly chance (few were seen in the act of falling) but their dark forms mean they will have caught the eye of meteorite hunters who scour desert sands and polar ice fields for rare rocks that can trade for tens of thousands of dollars.

- BBC.co.uk