Scientists may have found one of the legendary ‘Viking Sunstones’

Ancient Viking lore tells of a stone that could show them, unerringly, where the Sun was in the sky, thus giving them amazing navigational abilities. It was called a 'Sunstone'. Since none have ever been found at Viking sites, it has remained an artifact of legend, but a stone found inside the wreckage of a ship in the English Channel may have brought the legend into reality.

Sunstones are first mentioned in the Viking saga of Saint Olaf, written in the 13th century. This stone was discovered in the wreck of the Alderney, a warship that sank off the Channel Islands in 1592. Located near some other navigational instruments, this small geometric crystal tested as Icelandic spar, a form of calcite crystal that is believed to be what Vikings used for their sunstones, and it's specific shape gives it some very interesting qualities.

[ Related: Crystal found in English Channel may be fabled Sunstone ]

Holding a piece of this rhombohedral-shaped crystal up to look through it, you will see a double image of whatever is on the other side. However, if you rotate the crystal, the two images will eventually merge, and when they do, the crystal will be pointing east-west. This would give whoever had one a great reference point for navigation, even on a cloudy day.

"In particular, at twilight when the sun is no longer observable being below the horizon, and the stars still not observable, this optical device could provide the mariners with an absolute reference in such situation," says the study, published this week in the journal Proceedings of the Royal Society A, according to LiveScience.

[ More Geekquinox: Football field-sized asteroid zips by Earth this weekend ]

This particular crystal has been hopelessly polluted by minerals over the years spent at the bottom of the Channel, so it will never be useful as a navigation, but previous studies have shown that it is possible to use calcite crystal for this purpose, and that shards of calcite have been found at Viking settlements.

Geek out with the latest in science and weather.
Follow @ygeekquinox on Twitter!