Via the BBC.

A crystal found in a shipwreck could be similar to a sunstone – a mythical navigational aid said to have been used by Viking mariners, scientists believe.

The team from France say the transparent crystal may have been used to locate the Sun even on cloudy days.

This could help to explain how the Vikings were able to navigate across large tracts of the sea – well before the invention of the magnetic compass.

However, a number of academics treat the sunstone theory with scepticism.

The team from the University of Rennes in France say they found the crystal while examining the wreck of a British ship sunk off the island of Alderney – in the English Channel – in 1592.

An oblong crystal the size of a cigarette packet was next to a pair of dividers – suggesting it was part of the navigational equipment.

It has now been shown that it is of Iceland spar – a form of calcite known for its property of diffracting light into two separate rays.

Testing a similar crystal, the scientists proved that by rotation it was possible to find the point where the two beams converge – indicating the direction of the Sun.

They say it works on cloudy days, and when the Sun has set.

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13 Comments | Leave a comment
  1. Kitten says:

    Anyone see the new “Vikings” drama on the History Channel this past Sunday? Came on after the “The Bible” miniseries. Looks pretty interesting if you’re into Vikings, I guess. Anyway, the main character secretly introduces a device that is able to detect the direction of the sun, even when it isn’t shining. He will use the device to sail to the West to plunder new lands while his nemesis sails to the barren lands in the East. Can’t remember if the device was the sunstone though.

    • Cernunnos81 says:

      Loved that, even went so far as to watch the “First Look” of episode 2. That show is kick ass. I like that they’re showing parts of the society that are often overlooked. Yes, the device is a sunstone.

      I won’t drool to hard over Ragnar’s wife, but that is a fine woman, and strong. Might do the girls some good to see that women could thrive even in a patrirachal society like that. Well, semi-patriarchal. A wife could divorce her husband at the drop of a hat, and if he were captured in battle she could ditch him for a new model. Whereas, a man had to show good reason to divorce his wife and, if she were captured/kidnapped, he had to offer ransom and/or attempt to fight her captors to regain her before he could get a new wife.

      Another one of the things I enjoyed was seeing “viking justice”. They gave a brief explanation of the laws regarding murder. If it was self defense you could confess the fight to the first person you saw. They even had a rule for those travelling. You could pass the first or second house you came to, as they might be the homes of the victim’s family, but you could not pass the third. They even explained that if you had done what you were supposed to do you could pay restitution to the family. They didn’t name it, but it was called the Eric, which is the blood price. The case they showed was a man who didn’t do what he was supposed to and was sentenced to die, then asked how he wanted to die.

      I am also amused by the repeated appearance of “The Wanderer” aka Odin. As well as the reference to Odin giving his eye for knowledge. So, if you see someone that reminds you of Gandalf and he’s only got one eye and a raven on his shoulder, that’d be the boos man.

      Sorry for the rambling, always been a fan of the Vikings, both the culture and “Mythology”.

      • Kitten says:

        Thanks, Cern…ever the historian! 🙂 TAMs are a knowledgeable bunch, with many diverse interests.

        Shucks, I might even watch the next episode!

    • makeshifty says:

      It was a sunstone, but what I didn’t get was how they’d use the sunboard with it. The main character illustrated how the sunboard worked using a candle. Then the other guy asked, “What happens if the Sun’s not shining?” It was cloudy outside. He then went outside, and held up the sunstone. You could see the Sun disc through it, and he said, “There it is.” The thing was the sunboard depended on the Sun casting its shadow on a wooden disc. How does a sunstone help with that, I wonder?

      • Cernunnos81 says:

        The sunstone refracts a direct light source into 2 seperate rays. from a diffuse light source it allows you to find the brightest point. I would hazard that they used the single beam to shine onto the sun board, giving the same effect as full sun. (mind you this is only a semi-educated guess)

    • Sailing_J says:

      I did see it Kitten, and immediately knew what the article was talking about. What a concept! I’ve got to get my hands on one of these.

      • Kitten says:

        Makeshifty -Things that make you go…Umm. I think that’s why it’s “mythical”. I also must admit, I only watched the episode out of curiosity about the Vikings. Cern put that one episode into perspective and provided clarity.

        Sailing J -The sunstone “clearly” still holds that mysterious aura. However, I think that for the female, the interest is primarily centered around the beautiful gemstones one may receive from her significant other. 🙂

        You Guys…

  2. geezee says:

    Is there a sunstone to get us thru the next 4 years? #when4feelslike400

  3. Dave says:

    And these nasty boys were supposed to be ignorant ,raping, pilliging beasts. Yeah right.

    • Cernunnos81 says:

      Dave, these were some of the most technologically advanced folks on the planet, at that time. Their boats were better, their steel was better, their armor was better, their living conditions were pretty nice, they had laws that made sense and their women had rights.

      Were they bloodthirsty, nah. They raided for resources, cash and captives, both for ransom and for labor. Eventually they learned that, when you raid you have to wait a few years for your targets to rebuild and gather more resources, but if you Traded… you could go back Every year. Thus the Viking ship captain turned into the Dutch trader.

  4. Dave says:

    Hey Cernunnos81;
    Thanks for the unvarnished history lesson. I appreciate accurate information and a sensible reflection of the way it really was.

    • Cernunnos81 says:

      Dave old bean, I do love history to pieces in general, but at the same time I concentrate a tad on the Celts and Vikings. I kow more about them both as pre-Christian societies. The Vikings got kinda sad after their forced conversion, and many today are rebelling against the Christian beliefs and embracing the old ways.

      I like to study the old stories and myths of both cultures. There are similarities in the myths, as with any culture. Although I tend to be amused by the stories of Thor and his chariot and the goats that drew it, Tanngrisnir and Tanngnjostr. Tooth barer and tooth grinder. They were able to be killed and eaten every night, and Thor could ressurect them with his hammer. There’s an extra story involved that I won’t get into now, as it is a bit involved.

      Rambling again… sorry.

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