For centuries, ancient Norse myths spoke of a magical gem known as the sunstone, said to reveal the sun’s position even when it was hidden behind clouds or below the horizon. This legend, long thought to be mere folklore, has recently gained scientific backing. Researchers at the University of Rennes in Brittany have found evidence suggesting that these mythical sunstones were real navigational tools used by Vikings to traverse the seas with remarkable precision.
In March 2013, a team of scientists announced that a unique crystal found in the wreck of an Elizabethan ship off the Channel Islands might indeed be the legendary Viking sunstone. The shipwreck, dating back to 1592, contained a crystal along with navigational dividers, indicating its use as a navigational aid. The crystal, identified as Icelandic Spar or calcite, has the unusual property of double refraction, which can polarize light and help determine the sun’s position even in overcast conditions.
The principle behind the sunstone’s functionality is its ability to create a double image through light refraction. By rotating the crystal until the two images merge into one, the sun’s direction can be pinpointed with remarkable accuracy. This property would have been invaluable to the Vikings, who navigated vast and often treacherous waters long before the invention of the magnetic compass in Europe during the 13th century.
The Icelandic Spar crystal was found in the Alderney, an Elizabethan warship that sank near the Channel Islands. Although the crystal is now clouded and abraded, it once could have bent light in a way that was crucial for seafarers. Modern tests have shown that even in low light or twilight conditions, the crystal could provide an accurate reference for navigation. This would have been especially useful at times when the sun was below the horizon and stars were not yet visible.
The discovery aligns with the Viking saga of Saint Olaf from the 13th century, which mentions sunstones. Though no complete sunstones have been found at Viking archaeological sites, likely due to the Viking practice of cremating their dead, recent excavations have uncovered a fragment of calcite at a Viking settlement. This fragment offers tangible proof that some Vikings indeed used Iceland Spar crystals.
The use of sunstones could explain the Vikings’ reputation as formidable seafarers, capable of exploring and settling regions as far-flung as Iceland and North America between 900 and 1200 AD. The study authors speculate that even after the compass was introduced, mariners might have kept sunstones as a backup for navigation.
This discovery not only sheds light on Viking navigation techniques but also exemplifies how ancient myths often contain kernels of historical truth. The collaboration between archaeologists and scientists continues to reveal the ingenious methods our ancestors used to explore and understand their world.
