A recently discovered hunk of mineral may be an example of the legendary Viking “sunstone” that Norse seamen used to help them navigate the open ocean. Scientists from the University of Rennes in Brittany, France, have been studying the piece of crystal, found in the debris field of a late 16th century Elizabethan shipwreck off the Channel Islands in the English Channel.
The seafaring abilities of the Vikings were remarkable. In small vessels they sailed the North Sea, the Baltic, the Mediterranean and, of course, the North Atlantic. The Viking settlement at L’Anse aux Meadows at the northern tip of Newfoundland, Canada, is generally accepted proof that Viking sailors reached North America centuries before Columbus.
The Vikings accomplished these impressive passages without the help of sextants or chronometers or almanacs. The tools they used included simple “latitude hooks” for determining latitude. They also made extensive use of the bedrock of good navigation: dead reckoning. And, like Polynesian voyagers, they likely used experienced seamans’ eye for observing clues around them, such as marine life, birds and water color. The reports of a tool called a sunstone, however, were held by some to be a myth, not an actual navigation tool. The sunstone reportedly possessed a crystalline structure that allowed its users to determine the bearing of the sun. When combined with readings from a latitude hook, the sunstone acts as a sun compass and allows for setting east/west courses even when the sky was overcast.