A rough whitish, stone believed to be the fabled sand stone, which was used to assist the Vikings and other medieval sea-goers to navigate the high seas, was recovered from an Elizabethan shipwreck recently.
A Franco-British group is arguing that the Alderney Crystal, which is a chunk of Icelandic calcite found on a 16th century wreck, worked as a kind of solar compass. It is believed it allowed sailors to determine the position of the sun even if there was heavy cloud coverage.
It is also believed to contain the substance birefringence, which splits light beams in a way that can reveal the direction of their source with accuracy. While the Vikings may not have full understood the physics behind the phenomenon, it would not have presented a problem.
Albert Le Floch of the University in Rennes, in France said, “You don’t have to understand how it works. Using it is basically easy.”
The Vikings were stellar navigators who used the sun, stars, mountains and even migratory whales to guide them across the sea, however some have wondered at their ability to travel the long stretches of open water found between Greenland, Iceland and Newfoundland in modern day Canada. Le Floch is one of several persons who speculate that the calcite crystals were used as navigational aids.
However there are still skeptics like Donna Heddle, the Director of the Center for Nordic Studies, who described the solar compass as per hypothesis. She said, “There’s no solid evidence that that device was used by Norse navigators,” she continues. “There’s never been one found in a Viking boat. One cannot help but feel that if there were such things they would be found in graves.”
While she did acknowledge that the crystal came from Iceland and was found near a navigation tool, she argues that it could easily have been used as a magnifying device. Meanwhile Le Floch argued that one of the reasons no stones were found before because calcite degrades quickly and is vulnerable to acid, sea salts and heat. The Crystal found was originally transparent but the sea water turned it milk white.