Skip to comments.Researchers: We may have found a fabled sunstone (Update)
Posted on 03/08/2013 11:05:59 AM PST by Red Badger
A rough, whitish block recovered from an Elizabethan shipwreck may be a sunstone, the fabled crystal believed by some to have helped Vikings and other medieval seafarers navigate the high seas, researchers say.
In a paper published earlier this week, a Franco-British group argued that the Alderney Crystala chunk of Icelandic calcite found amid a 16th century wreck at the bottom of the English Channelworked as a kind of solar compass, allowing sailors to determine the position of the sun even when it was hidden by heavy cloud, masked by fog, or below the horizon.
That's because of a property known as birefringence, which splits light beams in a way that can reveal the direction of their source with a high degree of accuracy. Vikings may not have grasped the physics behind the phenomenon, but that wouldn't present a problem.
"You don't have to understand how it works," said Albert Le Floch, of the University in Rennes in western France. "Using it is basically easy." Vikings were expert navigatorsusing the sun, stars, mountains and even migratory whales to help guide them across the seabut some have wondered at their ability to travel the long stretches of open water between Greenland, Iceland, and Newfoundland in modern-day Canada.
Le Floch is one of several who've suggested that calcite crystals were used as navigational aids for long summer days in which the sun might be hidden behind the clouds. He said the use of such crystals may have persisted into the 16th century, by which time magnetic compasses were widely used but often malfunctioned. Le Floch noted that one Icelandic legendthe Saga of St. Olafappears to refer to such a crystal when it says that Olaf used a "sunstone" to verify the position of the sun on a snowy day. But that's it. Few other medieval references to sunstones have been found, and no such crystals have ever been recovered from Viking tombs or ships. Until the Alderney Crystal was recovered in 2002, there had been little if any hard evidence to back the theory.
Many specialists are still skeptical. Donna Heddle, the director of the Center for Nordic Studies at Scotland's University of the Highlands and Islands, described the solar compass hypothesis as speculative. "There's no solid evidence that that device was used by Norse navigators," she said Friday. "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." She acknowledged that the crystal came from Iceland and was found near a navigation tool, but said it might just as easily have been used as a magnifying device as a solar compass. Le Floch argued that one of the reasons why no stones have been found before is that calcite degrades quicklyit's vulnerable to acid, sea salts, and to heat.
The Alderney Crystal was originally transparent, but the sea water had turned it a milky white. Le Floch's paperwritten with Guy Ropars, Jacques Lucas, and a group of Britons from the Alderney Maritime Trustappeared Wednesday in the Proceedings of the Royal Society A.
Read more at: http://phys.org/news/2013-03-fabled-sunstone.html#jCp
This photo taken in Alderney, one of the Channel Islands, dated June 2012 and released on Friday March 8, 2013 by scientist Guy Ropars shows the Alderney Crystal, a piece of calcite. Researchers say the rough, whitish crystal recovered from the wreckage of 16th century English warship may be a sunstone, a special kind of mineral believed by some to have helped medieval seafarers navigate the high seas. (AP Photo/Guy Ropars)
Release the Kraken!!!
A natural beam splitter?
“Le Floch noted that one Icelandic legendthe Saga of St. Olafappears to refer to such a crystal when it says that Olaf used a “sunstone” to verify the position of the sun on a snowy day.”
I hope that all this speculation regarding sunstones isnt due to a single reference in some guy’s journal. If thats the case sunstones have about the same credibility as bigfoot. It would also reinforce my suspicion that archaeologists have far too much time on their hands.
Many stone have birefringence but I was taught Iolite (Cordierite) was use as “sunstones” by Vikings. They were used in pairs as crossed polarloid filters to produce a dark field similar to welding goggles becuase of the the gemstone’s extreme pleochroism, not birefringence.
I read a sci-fi story once with a female archaeologist digging up an old Viking boat with it's crew and the men came to life. After a few days of driving the men around and having them stay at her apartment and humorous interactions and experiences, she asked why they weren't more dazzled at the baffling technology that they were seeing for the first time, one of the Vikings simply stated that, "it was no matter, we had magic in our time also".
Came looking for nearly free and limitless energy. This thread is a Total Heinlein Fail....
Can the suns position in the sky not be estimated by the time of day? Therefore an hour glass could track the Sun from daylight to dark? As long as East and West can be defined?
Who pays for archeologists? Why you do. Most of them are supported by taxes in one form or another. The reason they have too much time on their hands is that they don't have to produce a competitive product to get paid. Sunstone BS doesn't have to be marketable to get the originator paid.
Yes. It's sometimes called "Iceland Spar". Tourist traps and novelty shops of the sort that sell or used to sell various mineral samples commonly sell small pieces of it.
It splits refracts vertically and horizontally polarized light differently, producing a split image. A good sample will be quite clear. Centuries of immersion in seawater would not be good for it.
Ahhh ... that's the big problem, isn't it? Defining longitude is not easy. The development of precise, portable chronometers was driven by the need for such devices to determine longitude.
“The reason they have too much time on their hands is that they don’t have to produce a competitive product to get paid.”
That’s not entirely true. They are supported by grants which are competitively awarded against the proposals of others. My problem with archaeologists is that almost all the time the results of their studies are useless. Did a certain dinosaur have feathers, did the vikings use a sunstone? What sort of wood did some extinct indian tribe use to make a spear? Who gives a Cr@p except that it satisfys someones idle curiosity. It has no practical value, and most of the time the conclusions are based on guesswork and speculation.
“If we confined ourselves solely to pursuits that had calculable practical value, life would be very unpleasant.”
Agreed. I do lots of things that have no practical value, but I use my own money.
And they have dirty minds, too...
“Brooklyn Attitude” = “Never need fear sunburn on scalp.”
That’s the kind of guy arrows were made for.
“a sunstone, the fabled crystal ....”
The ambiguous meaning (in this context) of “fabled” seems to imply that there is some doubt about the existence of sunstones. The statement is partially accurate, if “fabled” is taken to mean “made famous in fables”. It is completely wrong, if it is supposed to mean “exists only in fables”.
Sunstones do exist — that’s an indisputable fact. There are also accounts of their use by Viking navigators. Now, it seems that these accounts are likely “historical”, and not merely “fables”. The statement should be changed to: “a sunstone, the crystal made famous in historical accounts of Viking navigation”.
Have you read the book Longitude? I really enjoyed it.
Been reading the Tom Holt, have ye?
I googled him and you are right, the book is “Who’s Afraid of Beowulf?”
It was a fun read and I recommend it to people.
"Sunstone" is a popular current misnomer for other varieties of feldspar, particularly material from India with bright spangles of mica, and for beautiful copper-infused material of many hues from Oregon, USA. Another gem-grade spangled variety occurs in Tanzania.
As used in Viking lore, the word "Sunstone" referred to some kind of stone (believed by some to be the mineral Iolite) that was used to find the sun on cloudy or foggy days. That name has nothing to do with current usage.
Calcite ("Iceland Spar")is an entirely separate mineral. It is also doubly-refractive and splits light into two beams traveling at different angles through it. One of my friends has created this information about it the fabled Viking "Sunstone": The Viking Compass
Yes, I have. Good book.
Can the suns position in the sky not be estimated by the time of day? Therefore an hour glass could track the Sun from daylight to dark? As long as East and West can be defined?Of course. That is what makes navigation by the stars and sun possible. The whole point of the sunstone is to compare the observed elevation of the sun to what it ought to be at any given observation.
The sun's elevation at (for example, high noon) is known for every latitude for every day of the year and that data can be set out in tables to be published for the use of navigators.
Then the navigator can observe the elevation of the sun at its zenith and consult the table to see his latitude.
Longitude is a tougher proposition. For that, you need to have a highly accurate clock (a navigator's marine chronometer) and a much more complex set of tables to set out elevations for the major stars in your hemisphere, again in relation to the time of day and the day of the year.
The clock would be set for an exact time at a known reference point on the earth (for example at Greenwich Observatory) and the clock must maintain its accuracy throughout the voyage.
The accuracy of the position fix will depend on the accuracy of the clock and the accuracy of the sextant that is used to obtain several stars elevations and the skill of the navigator to take accurate measurements.
Observing three stars wull produce curves lines on a chart of the surface of the globe together they make a "cocked hat" within which is the navigator's calculated position.
The greater the accuracy of the clock and the sextant and the accuracy of the navigator's obseravation, the smaller is the cocked hat.
Latitude was not a major problem for the Vikings. Longitude was a problem.
Caveat: I am grossly over-simplifying here
I guess the main observation for me was From Norway you sail west till you see land and visa versa, or north and south! They weren’t looking for a needle in a haystack! Just land fall! IDK!
Sun Stone Ping
I hope theirs were more useful that ours.
You might like this:
|GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach|
Thanks Red Badger.
That is a very pretty rock.
I didn’t expect that!
haha that’s a great line
Interesting reading in fact. I have coursed the Northern Meadows of Newfoundland, and they are a lot more hospitable than Greenland or Iceland.
But the last 20 years of solar driven warming shows us that the medieval warming period may have put the Vikings into contact with native Canadians a long time ago.There are also oral tradition legends about blond haired , blue eyed native Canadians.
great link, thanks.
There is also the historical record...
When Lewis & Clark wintered in North Dakota, they were hosted by blond haired, blue-eyed Mandan "indians".
I suspect this particular remnant would be associated with Minnesota's Kensington Runestone, but they likely would've originated in Greenland or Newfoundland.
Probably from Snorre Sturlasson. He was very accurate.
Some years ago, I visited the Three Rivers Petroglyphs in New Mexico -- between Carrizozo and Tularosa, at the foot of the Sacramento Mtns overlooking the Tularosa Basin.
The site is a jumble of igneous rocks and boulders, generally about 3-5 ft high. The petroglyphs themselves are in profusion, but faded and somewhat indistinct -- to see them well, you really have to let your eyes adjust.
At one point, I sat down to rest in the shade of one boulder and looked at the boulders opposite that were highlighted by direct sun.
Suddenly, the faint forms fell into sharp focus. And one of the glyphs that stood out was a Viking ship in profile -- the high prow and stern, the square sail, the row of round shields along the gunwales.
The Three Rivers petroglyphs reportedly date to 1000-1400 AD. How did such an accurate depicition of a Viking ship appear in Southern New Mexico during this period if someone hadn't actually seen one?
Did the "long ships" actually make it to Vancouver Island...???
Or did an adventurous Viking somehow make his way from Lake Winnipeg to the Pacific coast...???
It’s been a while since I first read all of this website, maybe the answer is there in part. There’s a fascinating section on Easter Island also, it shows structures that are remeniscent of structures on the island of St Kilda, in the Atlantic, off the New Hebredes. I’m inclined to think the Vikings (I think of them as Norwegan sailors) owned the oceans in the Northern hemisphere.
It's on the island of St Kilda, not shown on the map, that one finds undated structures such as this, named cleits, supposedly constructed for storage of goodness knows what:
Which appear in similar appearance to structures found on Easter Island, described as chicken coops!
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