Sunstone Unearthed From Sixteenth Century Shipwreck

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Sunstone Unearthed From Sixteenth Century Shipwreck

Posted by samzenpus on Wednesday March 6, 2013 @02:01PM from the guided-by-the-light dept.

sciencehabit writes "In 1592, a British ship sank near the island of Alderney in the English Channel carrying an odd piece of cargo: a small, angular crystal. Once it was brought back to land, a few European scientists began to suspect the mysterious object might be a calcite crystal, a powerful 'sunstone' referred to in Norse legends which they believe Vikings and other European seafarers used to navigate before the introduction of the magnetic compass. Now, after subjecting the object to a battery of mechanical and chemical tests, the team has determined that the Alderman crystal is indeed a calcite and, therefore, could have been the ship's optical compass. Today, similar calcite crystals are used by astronomers to analyze the atmospheres of exoplanets—perhaps setting the stage for a whole new age of exploration."

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In a perfect world by binarylarry · 2013-03-06 14:03 · Score: 5, Funny

I hope when it was unearthed the finder said something like "By Odin's Beard! Tis the SUNSTONE that was foretold in the prophecy!"
At least that's what I would have done. 3

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1. Re:In a perfect world by robthebloke · 2013-03-06 14:16 · Score: 4, Funny
  
  ... and yet everyone else would hear that as:
  Blurgh, Blurgh. Blurgh, blurgh... Bubble, bubble, bubble.... shhhhhheeeeeerssshk... Blurgh, blurgh. Blurgh, blurgh.... Bubble bubble bubble
2. Re:In a perfect world by mcgrew · 2013-03-06 14:56 · Score: 4, Interesting
  
  That sounds like Vogon, anybody got a babelfish?
  This interested the hell out of me, I'd never heard of it before. Wikipedia says it was used to find the sun on a cloudy day, which would indeed be very useful to navigators with no compasses.
  It also said it's Oregon's official gemstone. No sun or magnets in Oregon?
  THIS is why I love slashdot! Who knew? Not me!
  
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  Free Martian Whores!
3. Re:In a perfect world by Nidi62 · 2013-03-06 15:03 · Score: 5, Interesting
  
  This interested the hell out of me, I'd never heard of it before. Wikipedia says it was used to find the sun on a cloudy day, which would indeed be very useful to navigators with no compasses.
  I find the timing of this story rather interesting, because the History Channel's newest special miniseries Vikings just started up this past Sunday. In it, the main character reveals to his brother a sunstone that a wanderer had given him. He then proceeds to find the sun through the clouds for his brother, who did not believe that the stone would work.
  
  --
  The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
4. Re:In a perfect world by rossdee · 2013-03-06 15:43 · Score: 1
  
  "That sounds like Vogon, anybody got a babelfish?"
  Believe me if it is Vogon (poetry) you don't want to hear the translation.
  Anyway I wonder how long it will be before someone digs one up around here.
  (I live less than 50 miles from Alexandria, MN)
5. Re:In a perfect world by ColdWetDog · 2013-03-06 16:57 · Score: 1
  
  A MØØse once bit my sister.
  
  --
  Faster! Faster! Faster would be better!
6. Re:In a perfect world by dougisfunny · 2013-03-06 17:07 · Score: 1
  
  He probably got Odin's beard confused with Durin's beard.
  
  --
  This is not the funny you're looking for.
7. Re:In a perfect world by unrtst · 2013-03-06 17:27 · Score: 1
  
  I find the timing of this story rather interesting, because the History Channel's newest special miniseries Vikings...
  I was about to say the same thing!
  Oddly, it's the second reference from that series that I ran into today. The other is the Shield Maidens. I just hit a part in the book, "The Mongoliad: Book One" that mentions them. I had never heard of them before the series or the book. (yeah, it's not quite as coincidental timing-wise, since the book was released well before the series, but it was a surprising coincidence to me nonetheless)
8. Re:In a perfect world by riverat1 · 2013-03-06 17:46 · Score: 2
  
  Like you I looked it up on Wikipedia and was confused. The Sunstone article said it was feldspar, not calcite as in the post. Then I dug deeper and the Sunstone (medieval) article says the original sunstone used for navigation was calcite like Iceland spar. I don't know if the feldspar version could be used for navigation or not.
  BTW, we don't need the sunstones (feldspar version) here in Oregon, we just have a supply for those that do.
9. Re:In a perfect world by Anonymous Coward · 2013-03-06 19:19 · Score: 1
  
  Wikipedia says they can find the sun's azimuth even when the sun is below the horizon!
  http://en.wikipedia.org/wiki/Sunstone
  The name derives from sunstones believed to have been used for navigation in the Middle Ages because their optical properties allow the azimuth of the sun to be detected even when the sun is below the horizon, with an accuracy within a degree or so.[1][2]
  Does this mean at night?
10. Re:In a perfect world by ryzvonusef · 2013-03-06 20:25 · Score: 2
  
  No, you ninny, everyone know you use a Sun stone to evolve to evolve their pokemon! ;p
  
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11. Re:In a perfect world by lxs · 2013-03-06 23:38 · Score: 4, Funny
  
  The second sentence should begin with a capital 'Thorn' but some reason the /. posting system does not like that symbol and zaps it.
  You have unearthed the fabled "ASCII only website" a beast of legend! It is said that ancient people communicated this way long before Unicode was invented.
12. Re:In a perfect world by mcgrew · 2013-03-06 23:39 · Score: 1
  
  If you think Vogon is bad, you should hear that one British kid...
  I wonder how long it will be before someone digs one up around here.
  It isn't that they're rare, it's that we found evidence that the stories of this "magic" stone were true.
  
  --
  Free Martian Whores!
13. Re:In a perfect world by MitchDev · 2013-03-07 01:28 · Score: 1
  
  You beat me to it....
14. Re:In a perfect world by Gilmoure · 2013-03-07 03:15 · Score: 1
  
  So... no thermo luminescence; no little fuzzy things begging for estefee?
  
  --
  I drank what? -- Socrates
15. Re:In a perfect world by shaitand · 2013-03-07 03:44 · Score: 1
  
  You can buy them all day long on ebay. They suspected these were used for navigation, this is interesting because it is physical evidence to support that.
16. Re:In a perfect world by bill_mcgonigle · 2013-03-07 05:03 · Score: 1
  
  needs more 'verily'.
  
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  My God, it's Full of Source!
  OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
17. Re:In a perfect world by Tuidjy · 2013-03-07 06:35 · Score: 1
  
  It means before sunrise and after sunset, but not too long either way. Refraction by the atmosphere.
  
  --
  No good deed goes unpunished...
18. Re:In a perfect world by X0563511 · 2013-03-07 07:16 · Score: 1
  
  Twilight.
  
  --
  For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
19. Re:In a perfect world by Rich0 · 2013-03-07 08:24 · Score: 1
  
  Might be worth noting that the operation of the stone in the show is fairly different from the description on wikipedia. In the show they basically hold it up to the clouds and see the sun through it. In Wikipedia they describe having to adjust the angle the stone is held at to detect circles in the sky and use that to locate the sun. Whether they are equivalent descriptions I cannot say. When they demonstrated the stone on the show I guessed it was calcite and had something to do with the polarization of light, but I couldn't see how it would behave in quite the way they demonstrated it, and I might have been right about that much.
20. Re:In a perfect world by nightfury · 2013-03-07 09:40 · Score: 1
  
  You hadn't heard this term in the Lord of the Rings series?
21. Re:In a perfect world by RivenAleem · 2013-03-07 23:36 · Score: 1
  
  Monarch Butterflies can do the same thing, they navigate by the position of the sun, but can locate it even on a cloudy day.
  Another amazing fact about monarch butterflies, their migratory pattern lasts 3 generations, so no single butterfly knows, or has ever done the whole trip.
22. Re:In a perfect world by bbsalem · 2013-03-08 09:31 · Score: 1
  
  The way this works is that the atmosphere polarizes the light from the sun, and that can be detected before the sun rises or after it sets. On an overcast day, the polarization can be detected as well, giving a way to determine the azimuth of the sun even when it can't be seen by eye.
  Calcite is birefriigant, meaning that rays of different polarization pass through a single crystal with rhombic cleavage plans in two paths, which you can see. I would assume that two crystals attached by with different orientation of their crystallographic axies would produce interference which can easily be seen. That is the principle of the polarizing microscope in which one of the polarizers is allowed to rotate freely over the other producing the shifting interference colors.
  If you are curious, get a piece of clear calcite with clean cleavages and look through it in various directions. You will soon see the birefrigance. It is not necessary to get a complete crystal, with euhedral faces, as they are usually pitted anyway, and large crystals cleaved in the right way are easy to get.
Prime example of scientific tunnel-vision? by the+biologist · 2013-03-06 14:04 · Score: 5, Interesting

I hope that by "battery of mechanical and chemical tests", they meant "showed it to a geologist for five minutes". There are a number of minerals which can mimic calcite to the untrained eye, but they're easy for the specialist to distinguish.
1. Re:Prime example of scientific tunnel-vision? by Anonymous Coward · 2013-03-06 15:11 · Score: 5, Informative
  
  No kidding. 1) it has a hardness of 3 on Mohs hardness scale, 2) it fizzes in acid, 3) it has 3 perfect non-90-degree (rhombohedral) mineral cleavages, etc. Five minutes? More like under one minute. Even the photo is enough to tell that's very probably calcite.
  On the other hand, maybe they needed non-destructive tests, which would make it slightly trickier (hence 5 minutes).
2. Re:Prime example of scientific tunnel-vision? by Anonymous Coward · 2013-03-06 16:26 · Score: 5, Informative
  
  Actually, according to the abstract, they were trying to determine what happened to the crystal while it sat on the seafloor. Alteration from 400+ years of contact with seawater (plus sand abrasion) changed the physical and optical properties somewhat.
3. Re:Prime example of scientific tunnel-vision? by Zyrill · 2013-03-06 17:40 · Score: 3, Interesting
  
  Actually, a crystal's basic physical and optical properties do not change even when it is eroded: one unit cell of the crystal has all the determining characteristics that a macroscopic sample would have. Given, it takes some training to tell a rough diamond apart from quartz, but that's what mineralogists and material scientists are for. Oh and one more thing: if it was at least a little transparent, the most readily distinguishable characteristic of calcite is that it's birefringent (check: Wikipedia if you do not know what that means).
4. Re:Prime example of scientific tunnel-vision? by Anonymous Coward · 2013-03-06 18:10 · Score: 5, Informative
  
  As it happens, I'm a geologist. There's a difference between alteration and erosion. What the article refers to is the exchange of calcium and magnesium between the crystal and seawater (ratios of Ca and Mg move towards equilibrium with the ocean chemistry). That kind of substitution does change your unit cell a bit; which will alter the properties slightly. It would still be calcite (which is ridiculously easy to identify, as you say); just not quite the same calcite it was before it was dunked.
  Reading the summary, it sounds like the calcite had been altered to the point where it couldn't be used as a sunstone (cloudy and scratched). The tests were to determine if the crystal would have made a good sunstone prior to being soaked/abraded.
5. Re:Prime example of scientific tunnel-vision? by Grizzley9 · 2013-03-07 02:41 · Score: 4, Funny
  
  By Odin's Beard! An Anonymous Coward post at Score:5, Informative!
6. Re:Prime example of scientific tunnel-vision? by tehcyder · 2013-03-07 03:37 · Score: 1
  
  the most readily distinguishable characteristic of calcite is that it's birefringent
  That sounds like some particularly complicated sexual practice. I'm not going to spoil things by looking up what it actually means, as it will certainly be much, much duller.
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
7. Re:Prime example of scientific tunnel-vision? by Anonymous Coward · 2013-03-07 04:07 · Score: 1
  
  Plenty of minerals are birefringent, but calcite is notable because it is so strongly birefringent. Make up your own joke :-)
  Anyway, if you think that's impressive, calcite also has 3 perfect cleavages.
  Careful looking that one up.
8. Re:Prime example of scientific tunnel-vision? by charlesj68 · 2013-03-07 08:33 · Score: 1
  
  A harbinger of Ragnarok, to be sure.
9. Re:Prime example of scientific tunnel-vision? by RivenAleem · 2013-03-08 00:02 · Score: 1
  
  By Odin's Beard! This is a meme I can get behind!
lost knowledge? by k6mfw · 2013-03-06 14:15 · Score: 4, Interesting

In a discussion I had with a friend the other day about how did Vikings navigate? Mostly poor weather (no star sightings) and very close to magnetic north pole (compass is useless), or they only traveled part of year when weather was not really bad. One story I heard is they used pressure as a means of navigation. Huh? don't ask me, that is what someone else said. But since that was 1000 years ago, that knowledge is lost so all we have is speculation. Interesting to consider What If... they continued further south and settled in sunny Florida?
In the book "From Vinland To Mars" published in 1970s it said many Scandinavian men were "landless sons" since first born son inherits the land, and there is not much farmable real estate in those areas. So these landless sons don't have much career opportunity except join the Viking Navy and plunder rest of Europe but there was also motivation to go west to find other places to settle.

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1. Re:lost knowledge? by alen · 2013-03-06 14:21 · Score: 2
  
  Same reason why people went west in the USA
  The year 1000 was in the middle of another global warming cycle and there were too many people for some parts of the world. So they went out to conquer, rape and pillage other parts of the world.
2. Re:lost knowledge? by smegfault · 2013-03-06 14:24 · Score: 2
  
  In those times there was simply not enough land to give each son a piece of the family tracts of land, so yeah, venturing out to sea was basically their only option. It is however an astonishing testimony to their persistence and ability to withstand hardships that they landed on another continent. Having to go cross-continent in a modern flying machine isn't exactly my idea of a fun time, even with all my electronic gadgets - I can't imagine what it must be like to be on a wooden ship for a year or more, without any clear purpose or target and very little distraction. Optical compass or not - the Norsemen pulled of some spectacular achievements.
3. Re:lost knowledge? by hairyfish · 2013-03-06 16:00 · Score: 1
  
  Ok that that answers the Viking's story, how about the Polynesians?
4. Re:lost knowledge? by tragedy · 2013-03-06 16:09 · Score: 1
  
  That involved following/riding on whales, didn't it?
5. Re:lost knowledge? by wvmarle · 2013-03-06 17:37 · Score: 2
  
  Even with the sunstone, I still wonder how it is actually used in navigation.
  The sunstone obviously determines the direction of where the sun is located - which can basically be anywhere, particularly in summer in the arctic when the sun doesn't set. I know how to get my heading using the sun (unless it's too high above me, like around midday in summer as I'm a hair south of the Tropic of Cancer) and a watch - it basically relies on knowing where the sun is at that moment, and knowing the actual time.
  So now the vikings may have had a way to tell where the sun was, with rather high accuracy, without knowing the time that information is rather useless. So something is definitely missing there. The same accounts for this 1592 vessel, no accurate clocks available yet.
  For shortish crossings (a few hours at most out of sight of land) this may work just fine, from experience a seafarer may be able to compensate for the change of direction of the sun. But for anything longer (Norway to Iceland or even to the Americas) that won't work so well any more.
6. Re:lost knowledge? by able1234au · 2013-03-06 18:50 · Score: 4, Interesting
  
  I don't think they went from Norway to Newfoundland. Instead they went Norway -> Orkneys -> Iceland -> Greenland -> Newfoundland. So while still an amazing achievement, it was more like one more hop, mostly west, so tracking the sun is useful for that. The vikings from Greenland that sailed down to L'Anse aux Meadows had already been sailing west from Greenland to trade with the natives (the Dorsets?) and just kept going further. L'Anse aux Meadows was a long way from Greenland and the Indians further south would have been tough to fight, given the population of Greenland was small. So you can see why they did not establish large settlements there. If word had gotten all the way back to Norway and the multiple hops were easier then perhaps more would have settled but it didn't look as attractive as it did for the rest of Europe 500 years later.
7. Re:lost knowledge? by Phrogman · 2013-03-06 19:50 · Score: 5, Informative
  
  Its worth noting that while we know the Vikings for their raiding and pillaging, they were in fact some of the most successful traders in Europe at the time. They were also very good and competent craftsmen.
  What we get is the Evil Vikings (tm) version as related by the Christian Church, from when they were (gasp) Pagans and not subject to the rule of that church. Once they had been forced at sword-point to convert to Christianity they became more acceptable. Not that old Norse religion was anything to be particularly happy about mind you. My point is that the Vikings sailed their ships around Europe down into the Mediterranean, conquered Russia (the Rus were effectively Norseman), served as the Imperial Bodyguard for the Byzantine Empire etc. They didn't just destroy and pillage - and most of the other peoples in Europe did a lot of the same thing anyways.
  The Sunstone is a neat idea if true though. I would have bet the Norse navigated mostly by the stars myself, and that they tended to stick to being within sight of land most of the time as most people did prior to the invention of modern navigation.
  
  --
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8. Re:lost knowledge? by expatriot · 2013-03-06 21:52 · Score: 1
  
  I can't find an image for it now, but I have seen a primitive portable sundial disk. I have a modern version as a novelty.
  If you know north, you can find the time and vice versa. Aha you say, how do you know the time? Well in a "primitive" society, people could develop a sense of what time in was. This could be refined by practicing with the sundisk on land.
  In an earlier age, railway engineers were said to be able to guess the time to a few minutes and only checked their watches for the minute.
  If this crystal made it more reliable to find the sun, that made it easier.
  Some other techniques are obvious in retrospect such as changed cloud formations over islands.
9. Re:lost knowledge? by jabuzz · 2013-03-07 00:32 · Score: 1
  
  Vikings have a reputation for being "evil" because they luted,raped and pillaged large areas of the British Isles. Sure they might have done other smart things, but that does not detract from the fact that they where nasty pieces of work.
  Invoking Godwin's Law the Nazi's had lots of wonderful technological stuff as well. They where however still evil bastards.
10. Re:lost knowledge? by Anonymous Coward · 2013-03-07 00:58 · Score: 2, Funny
  
  Vikings have a reputation for being "evil" because they luted,raped and pillaged large areas of the British Isles.
  
  Thanks you for making my day there :) Luting (http://en.wikipedia.org/wiki/Lute) should indeed be considered evil!
11. Re:lost knowledge? by Anonymous Coward · 2013-03-07 01:17 · Score: 1
  
  Well, according to letters we have found from the time, the rape part might have been convinient lie. The danes were taller and blonder than the british, and they bathed regularly and braided their hair and beards. They settled part of Brittain in what became known as Danelaw, and was considered a nuisance because they could seduce even married women. They were later subject to a genocide and wiped out in Brittain.
12. Re:lost knowledge? by jbengt · 2013-03-07 02:28 · Score: 1
  
  So now the vikings may have had a way to tell where the sun was, with rather high accuracy, without knowing the time that information is rather useless. So something is definitely missing there.
  It's easy to tell when noon is from a sundial. And if you know the date and the elevation of the noon sun, you can tell your latitude. And if you know your latitude and the date, you can tell what time and what direction sunrise and sunset are. And if you know a few times, you can use an hourglass or something to tell other times. Not necessarily the most accurate, but all is not lost, even without a good timepiece.
13. Re:lost knowledge? by wvmarle · 2013-03-07 03:16 · Score: 1
  
  Sundials don't exactly work reliably on a boat.They are highly dependent on being in a fixed direction.
  Also these crystals are typically for overcast days, where you can't see the sun.
14. Re:lost knowledge? by tehcyder · 2013-03-07 03:42 · Score: 1
  
  In a discussion I had with a friend the other day about how did Vikings navigate?
  If you take a straight left from Scandinavia you'll either hit Britain (which you can plunder/settle) or if you're unlucky and miss it, you eventually get to Greenland then America.
  It's really not that complicated.
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
15. Re:lost knowledge? by tehcyder · 2013-03-07 03:45 · Score: 2
  
  That involved following/riding on whales, didn't it?
  I thought they followed swallows carrying coconuts, or something?
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
16. Re:lost knowledge? by tehcyder · 2013-03-07 04:01 · Score: 1
  
  Well, according to letters we have found from the time, the rape part might have been convinient lie. The danes were taller and blonder than the british, and they bathed regularly and braided their hair and beards. They settled part of Brittain in what became known as Danelaw, and was considered a nuisance because they could seduce even married women
  So, a bit like American GIs during WW2 in Britain?
  
  --
  To have a right to do a thing is not at all the same as to be right in doing it
17. Re:lost knowledge? by shaitand · 2013-03-07 04:05 · Score: 1
  
  Up is fixed, even on a boat. You can always find noon with a sun dial. By analysis of the shadow cast by a peg (similar to a sundial) you can calculate if you've deviated from a course provided you know what time it is and have a reference position to check against. The vikings would have known what time it was at least once a day.
18. Re:lost knowledge? by k6mfw · 2013-03-07 05:05 · Score: 1
  
  Not that old Norse religion was anything to be particularly happy about mind you.
  but then their religion has exciting characters you can use for comic books, i.e. Thor.
  
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  mfwright@batnet.com
19. Re:lost knowledge? by Sedated2000 · 2013-03-07 05:59 · Score: 1
  
  Remember there is a difference between a Viking and a Viking age Norsemen. The Vikings themselves had a bad reputation for being evil in large part because they were looting and committing massacres at peaceful monasteries such as Lindisfarne.
20. Re:lost knowledge? by angel'o'sphere · 2013-03-07 12:55 · Score: 1
  
  Oh, idiot mods around again? Already 2 down mods? For what exactly if I may ask?
  
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21. Re:lost knowledge? by angel'o'sphere · 2013-03-07 12:58 · Score: 1
  
  While you are strictly speaking correct.
  This is not what old school navigation was about. They only used the sun as compass ersatz.
  And this crystals are useful to find the suns position even under fog or clouds.
  See it this way: I want to sail strictly west. My latitude is irrelevant if I'm confident that I reach greenland as long as my course is good enough. Drifting to far south or to far north is my main concern ...
  
  --
  Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
22. Re:lost knowledge? by shaitand · 2013-03-08 06:38 · Score: 1
  
  You just provided one simple solution yourself. A simpler one would be to construct your dial of wood and put it in a deep bowl of water. Assuming the bowl is held down it shifts with the boat but the surface of the water remains level. Which is essentially the same thing you do with a compass. It isn't just the rocking of a boat but the improbability that you are holding your hand level. This would be a problem on land as well. Up is still up on a boat.
Sadly, not that sunstone by Aryeh+Goretsky · 2013-03-06 14:20 · Score: 4, Interesting

Hello

When I first saw the headline, I thought it was going to be a fossilized bioluminescent sunstone from H. Beam Piper's Little Fuzzy series of science fiction stories.

Still, a fascinating read, albeit not one as exciting as if H. Beam Piper's fictional sunstones had been found to exist in real life.

Regards,
Aryeh Goretsky

--
Dexter is a good dog.
1. Re:Sadly, not that sunstone by Anonymous Coward · 2013-03-06 22:17 · Score: 1
  
  Dear Aryeh Goretsky
  It looks like you're writing a letter.
  Would you like help?
  o Get help with writing the letter
  o Just type the letter without help
  [_] Don't show me this tip again
2. Re:Sadly, not that sunstone by Chris+Mattern · 2013-03-07 01:14 · Score: 1
  
  My god! They weren't Vikings, they were Space Vikings! That explains everything!
Hmm... by rusty0101 · 2013-03-06 14:42 · Score: 2

Since there appears to be at least two markets for calcite crystals, Astronomers, and I would expect the re-enactment community, I wonder if there is a means of creating either the variety needed by astronomers, or people interested in re-enacting voyages of vikings or others.
I would suspect that creating them would be potentially less difficult than creating man-made diamonds, but I haven't checked.

--
You never know...
1. Re:Hmm... by Billy+the+Mountain · 2013-03-06 15:52 · Score: 1
  
  Well, yeah, but it's Calcium Carbonate, and as such it is also useful in Tums(R) and drywall.
  
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2. Re:Hmm... by DerekLyons · 2013-03-06 17:15 · Score: 1
  
  I've never heard of anyone in the re-enactment community trying to navigate with one... It would be rather dodgy at best.
  But calcite isn't exactly rare, so there's no need to create it.
3. Re:Hmm... by rusty0101 · 2013-03-06 18:28 · Score: 1
  
  The question about creating it is not about simply generating calcite, or calcium carbonate, but in generating usable sized high quality crystals. Much of the stuff I've encountered in nature that is large enough to hold has crystals that are growing in multiple directions, with none discreetly large enough to be useful for either use. I'm quite certain that there are larger crystals that would be workable, but I'm wondering if the cost to grow high quality crystals might be low enough to make this into a workable product for either, or both markets.
  As far as re-enactment community trying to navigate with one, I would suspect that if it ever happens it will be someone showing what tools a viking may have used to successfully navigate the North Atlantic. Similar to proof of concept expeditions done by Thor Heyerdahl in the 40's, 50s, 60's and so. No they don't demonstrate exactly what ancient travelers may have done, however they do show whether current ideas are workable. I would expect that one of the kits included in the expedition would include gps and satcom gear.
  
  --
  You never know...
4. Re:Hmm... by DerekLyons · 2013-03-07 00:33 · Score: 1
  
  According to Wikipedia, it's mined. The "stuff you've encountered" is going to be a vanishingly small sample...
5. Re:Hmm... by jbengt · 2013-03-07 02:21 · Score: 1
  
  Drywall is made of Calcium Sulfate, not Calcium Carbonate.
Iceland Spar by kbahey · 2013-03-06 14:47 · Score: 5, Informative

I read about this a while ago, and it was fascinating. Appartently, the crystals polarized sunlight, even if it was through clouds and
Here are some links that may help:
The stone itself is calcite, Iceland Spar or the more complex Cordierite, also known as iolite.
Here is one account of how it could have been used:
Viking Sunstone
And here is another:
Viking Compass

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1. Re:Iceland Spar by An+dochasac · 2013-03-06 15:18 · Score: 5, Interesting
  
  I've done a lot of sailing on the Great Lakes and Irish Sea and I can tell you that cold water often brings a kind of dense low fog. There are times when we can see the tops of masts and blue sky above but because the sun is often low at these latitudes, we can't see where the sun is. But sometimes the fog was so bright, I'd wear sun glasses and then I did notice that the zenith blue sky was polarized. What's more, the digital watch we used for sailing was an LCD watch-- which means it polarized display. And the display did darken noticeably when turned at certain angles, so the reflected sky polarization was also discernible. At the time I wondered whether it could be used as a practical form of navigation, but we had a compass. A few years later Loran-C became popular addition to the compass as and then GPS. But when I heard about the theory that an Iceland spar sunstone might have been used for navigation in the high arctic, I'd give it the nod of plausibility. No it isn't as good as a compass, unless you're above 70 degrees magnetic latitude. No it wouldn't work well under conditions of total cloud cover or rain, might not work at all. But I'm sure this kind of low fog is at least as common in the arctic as it is at my latitude and if I were lost without a compass, GPS, Loran-C on a foggy day, you'd better believe I'd break out the sunstone if I had one.
2. Re:Iceland Spar by ScentCone · 2013-03-06 16:26 · Score: 5, Funny
  
  also known as iolite
  Which, as a man of world, you must know is the source of iocane powder. And because iocane comes from Australia, and Australia is entirely peopled with criminals, and criminals would try to fool wandering Vikings into thinking they could navigate with an iolite stone, we know we cannot trust this story they've put in front of us.
  
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3. Re:Iceland Spar by David+Gould · 2013-03-06 23:44 · Score: 1
  
  Ah, my kingdom for a mod point! Well done.
  
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4. Re:Iceland Spar by kbahey · 2013-03-07 03:43 · Score: 1
  
  Thanks for the morning smile ...
  Made my day already ...
  
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Re:Obscure Reference by game+kid · 2013-03-06 14:52 · Score: 2

It'll need 65 million years to regain its former luster after all that time down there.
Fortunately, that three-seater I double-parked outside can help...

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Bees! by Kaenneth · 2013-03-06 14:57 · Score: 1

I've read that Bees also use polarized sunlight to navigate.
1. Re:Bees! by tehcyder · 2013-03-07 04:17 · Score: 1
  
  I've read that Bees also use polarized sunlight to navigate.
  This new learning amazes me, Sir Bedevere. Explain again how sheep's bladders may be employed to prevent earthquakes.
  
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Aah That's Clever! by Greyfox · 2013-03-06 14:59 · Score: 3, Interesting

I imagine that was "magic" back in the day. Just a little Viking sorcery! I suppose the reverse of the rule is also true; any sufficiently antiquated "magic" must seem like technology. Imagine the wonder of the first person to notice this. Did they closely guard their secret? Did this knowledge give them an edge over their neighbors?
By the time you get to 1767, we're definitely leaning more toward "technology" (Though I didn't see this particular one mentioned in said document.) The math and devices are pretty well understood and the methods are shared openly. I'm sure I could find earlier documents if I were inclined to dig around a bit. This one actually popped up on a search for... something else I was looking for. Needless to say, I immediately decided I wanted to be a member of the Order of the Commissioners of Longitude. If they let me in I promise I'll sit in the back and be very quiet...

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1. Re:Aah That's Clever! by sFurbo · 2013-03-06 20:14 · Score: 1
  
  In the words of Agatha Heterodyne:"Any sufficiently analyzed magic is indistinguishable from technology. "
2. Re:Aah That's Clever! by shaitand · 2013-03-07 05:43 · Score: 1
  
  All the science can't really make things stop being magic. The "energy" that all the pieces are made of and the "force" that binds them are no less magic simply because we've given them labels and made rules for predicting and manipulating them. Someone who knows the ways of magic is a wizard. It's kind of amusing if you think about it, the quickest to scorn a supposed wizard would be our scientists and engineers but if scientists and engineers aren't our wizards who is?
  
  The ancients derived their 10 sphere tree of life representing major divisions of a universal white light, everything else is a smaller sub division of the frequency represented by a given sphere. If you try working the above numerically you'll quickly arrive at the relationship that results in 10. The universal light is the fundamental property of the wave. Sometimes they said vibration, sometimes light. The discrete spheres, discrete elements within them (like people, rocks, etc) are those vibrations viewed as particles. The cosmic light itself is a sort of great quark with every other discrete element being a subdivision or reflection of that quark and therefore also a quark. The relationship innate to a quark is that the nature of the universe is infinite possibility that when observed collapses into finite elements. Because you can add any number of finite elements with infinity and the result is still infinity you can try to view an infinite universe as finite elements but you must have at least one infinite element or else the equation that represents your universe no longer is equal to infinity. That's why we so often arrive at irrational numbers.
  
  The ancient magi of old knew all these. Not in these terms of course and they attempted to explain it all through the information they had in the day and ended up with the four corners of the world, the four elements and such. But the 4 was a given. Exists, does not exist, and might exist. You can't get simpler than that So three properties that are one thing. 3.1. But that means there is those three plus the thing itself. 3.14. That collection is another thing. 3.141. You can keep going... to infinity. But boy that number is sure beginning to look familiar... of course other paths of logic would have lead to different irrational numbers.
3. Re:Aah That's Clever! by The+Iso · 2013-03-08 10:49 · Score: 1
  
  There's some interesting history behind the Board of Longitude. It was formed in 1714 to judge prizes of up to £20,000 for a reliable method of determining longitude at sea (this was the scientific problem of the day, comparable to the modern search for a cure for cancer or theory of everything). In the early days, the board was flooded with crank proposals, and the commissioners' duties consisted of individually writing letters of rejection. When John 'Longitude' Harrison arrived in London in 1730 with plans for a clock that could keep accurate time at sea, the Board of Longitude, though it had been in existence for more than fifteen years, kept no headquarters and had never held a meeting. He sought out one of the board's most famous members, Edmond Halley, at the Royal Observatory.
  Halley knew that longitude could be determined from the time if a sufficiently reliable clock could be built, but that was a big 'if'. Not exactly qualified to judge Harrison's ideas, he sent him to the country's leading clockmaker, George Graham. Harrison went to see Graham in the morning; Graham invited him to stay to dinner and finally sent him off with a generous loan with no interest and no hurry to pay it back. Harrison took five years to build the sea clock, which performed beautifully on a test run to Lisbon, and he had every right to demand the test run to the West Indies required to claim the prize, but one person was unhappy with the clock: Harrison. He could build one even more accurate, he thought. And he could make it smaller. All he asked was £500 for further R&D.
  Harrison finally became satisfied with his clocks in the 1760s, around the same time that the lunar distance method became practical; the methods were widely used in conjunction until the price of marine chronometers came down. The Board of Longitude stuck around as publisher of the The Nautical Almanac—of which you've found the first edition—and was finally dissolved in 1828.
  Incidentally, Harrison's clocks were the subject of a memorable simile by Lord Byron, in Don Juan:
  
  Oh! She was perfect, past all parallel—
  Of any modern female saint's comparison;
  So far above the cunning powers of hell,
  Her guardian angel had given up his garrison;
  Even her minutest motions went as well
  As those of the best time-piece made by Harrison.
  
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  "You don't need a weatherman to know which way the wind blows." - Bob Dylan
AWRIGHT A SUNSTONE! by GameboyRMH · 2013-03-06 15:21 · Score: 3, Funny

Now I can get my Sunkern to evolve!

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1. Re:AWRIGHT A SUNSTONE! by Shadin · 2013-03-07 07:43 · Score: 1
  
  I am surprised by how far I had to scroll to find this.
Re:Oh yeah? by camperdave · 2013-03-06 17:21 · Score: 2

An Indian reservation? That's when they hold a seat for you at the nearest curry house?

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Don't tell Teraptus by mysidia · 2013-03-06 17:46 · Score: 1

Guard it closely...
The Mayan apocalypse, the sequester, and the zombie apocalypse all put together, are a walk in the park, compared to a dark wizard getting ahold of the Sunstone, and casting away the light...
Is it just me... by Yeff · 2013-03-06 18:26 · Score: 1

...Or is anybody else feeling all "questy"?

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Unearthed? by camperdave · 2013-03-06 18:26 · Score: 2

Actually, I'm kind of wondering how something on a shipwreck could be "unearthed"

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1. Re:Unearthed? by egcagrac0 · 2013-03-06 22:30 · Score: 3, Funny
  
  According to the many image-macros circulating, one cannot unsea.
Re:Oh yeah? by GigaplexNZ · 2013-03-06 19:15 · Score: 1

Yes, but he does need to be in a foreign country to be hit that way
Negative.
Interesting possibilities? by aklinux · 2013-03-06 21:25 · Score: 1

I personally never knew the Vikings had this optical compass thing going, but I see interesting possible ties to the Polynesians.

I spent about 20 years in the jewelry industry and I learned that calcite, at one time, was often mistaken for Diamonds. Calcite deposits are what gives Diamond Head in Hawaii it's name. The calcite was mistaken for Diamonds.

I wonder what the possibilities are that Polynesians used "Sun Stone" compasses to help find their way around the Pacific?
Coincidentally.. by slashmojo · 2013-03-06 23:25 · Score: 1

Just a few days ago the new TV series "Vikings" started and they happened to feature a sunstone.. http://www.imdb.com/title/tt2306299/
Well timed I'd say!
In case you missed it I'm sure it can be found at a certain viking torrent site.. ;) [which I don't condone of course]
I must be tired... by flargleblarg · 2013-03-07 02:16 · Score: 2

I misread that headline at first as:
Smartphone Unearthed From Sixteenth Century Shipwreck
1. Re:I must be tired... by museumpeace · 2013-03-07 04:33 · Score: 1
  
  don't you make fun of my SamsUNg stone!
  
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Any navigation device recovered from a sunken ship by museumpeace · 2013-03-07 04:29 · Score: 2

ought to be examined as an instance of what-not-to-do technology. I'll believe this is a navigation device when I see one on a FLOATING ship.

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See people by xyourfacekillerx · 2013-03-07 04:54 · Score: 4, Insightful

This is the kind of story that brings me to /. Less politics, more nerd stuff
Re:Any navigation device recovered from a sunken s by k6mfw · 2013-03-07 07:02 · Score: 1

Great quote, I'd mod you up but I already posted to this forum.

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