Viking Navigation via Iceland Spar on History Channel

Hello folks,

Saw a commercial for this last night. It appears that the History Channel will be playing an episode of Ancient Discoveries on 10:00 pm EST today (Thursday 20th). Check your local schedule. The commercial talked about how the Vikings may have discovered North America by using crystals to navigate. Not a lot of info in the commercial, but it appeared they were using the sun's rays reflected through a piece of Iceland Spar Calcite. May be interesting!?

Jen

Jennifer,
The trick is that light coming from 90 degrees opposite the sun will be polarized. Thus, even when the sun is below the horizon on those short Arctic nights when it's never quite dark, you could tell where the sun was. I have heard the same said of iolite, which is sometimes called Viking's Compass.

The program appears to be about ancient mining machines, at least here in Houston, TX. Should be interesting none the less.......

All,

The program was about Ancient mining and the Viking story came on about 30 minutes in for 15 minutes. For those that didn't catch it - it was interesting and new to me! The historians believed that the Vikings did indeed use Iceland Spar for sun navigation on cloudy days (in addition to long polar nights). Evidentally, you can use the double refraction of calcite to pinpoint the sun by rotating the crystals until the both sides of the double image are of equal intensity. I must admit I kind of lost how exactly the double image did that - maybe someone can help. They had two descendants of Leif go out in a little row boat off Iceland on a cloudy day at 11:30 pm (during a long polar day). The rowers went out until they couldn't see land and used the calcite to get them back to a specific point on the shore. They showed the Vikings rotating the calcite over an image, but again I was a little lost on how that actually translated to navigation - the show mentioned using ancestral knowledge. Still pretty neat for me.

I also liked the story on how Romans used hydraulic mining to mine for gold in Spain - destroying whole mountain sides with just falling water.

Jen

PS - Thanks Ray for solving my question with the 90degree angle. Now it makes a little more sense!



Edited 1 time(s). Last edit at 11/21/2008 04:58PM by Jennifer Nemitz.

This subject was covered in an excellent book by Leif Karlsen “Secrets of Viking Navigation”. The sunstone (a cleavage rhomb of “iceland spar” or optical calcite) indicates direction by means of the polarizing effect of the earth’s atmosphere on sunlight. As Ray indicated, the strongest polarization arrives from a sky directon at right angles to the sun’s direction. The Viking routes in the North Atlantic were often subject to dense fog. The sunstone could be used to locate the sun even on very cloudy days. Navigation was based on azimuth tables showing the position of the sun in the sky at various times of year, prior to the use of the compass by Europeans, around the 12th century. As Karlsen says:

“In order to use a crystal [of iceland spar] as a sunstone for finding the sun, a small black dot is placed at the center of the top surface, so it will face up when the stone is held overhead. View this dot from underneath by looking up through the stone while holding it flat (level to the horizon). You will notice the single dot appears as two dots when viewed through the stone. Align the… long side [of the crystal] to the brightest area of the sky. Upon rotating the stone back and forth in the horizonal plane, you will see that one image fades and the other becomes darker. When the two images appear to be equal in value note the position of the stone and the direction of a pointer aligned along the long side of the spar. The pointer will now be aligned to the true bearing of the sun. It is accurate to within one degree.”

I’ve experimented with this myself on cloudy days, with azimuth tables, and confirmed that it's quite accurate.



Edited 1 time(s). Last edit at 11/23/2008 02:33AM by Kelly Nash.

Excellent program I must say; very informitive, but a lot of the techniques shown I already knew a little something about........ B)

Found a pretty informative excerpt from the book mentioned in a later post [www.oneearthpress.com]
The author goes into good detail how it works and his own experience with this method. Pretty good stuff, makes me want to go out and get a chunk of the stuff.

The pdf mentioned in the previous posting and the book further up, the late Leif Karlsen's “Secrets of Viking Navigation” are very readable insights into the theory and technique. I highly recommend purchasing the book which is available from One Earth Press on a page further back from the pdf url above http://www.oneearthpress.com/

Leif was a professional navigator with a keen interest in how the Vikings navigated, his research took him back to Iceland and his homeland of Norway where he did primary research with the help of museum curators and scientists in both countries. He visited the Iceland Spar mines and obtained several prime specimens of which I am lucky to have one from him. There is more about Leif here at the Star Path Navigation site (a professional navigation school) http://www.starpath.com/news/leif.pdf

My interest (along with also being of Norwegian heritage and a sailor) is in the optical properties. We have been working with developing "teaching props" for students using the theory as a backdrop to investigating optical properties of anisotropic minerals. Several well known mineralogists have been enthusiastically involved, but most of all I am happy to promote Leif's passion for that history and his unique insights into navigation.

That aside, Iceland Spar is fascinating material -- there is a pdf at the top of one of my (unfinished) website pages on the project which might be of further interest http://www.nordskip.com/calciteoptics.html

Best wishes,
Elise

Thank u very much for this info. It was very useful for my mom and me who have islandic spar and were interested in it. Thx.

The information of how Icelandic Spar was used by Norse and Danish navigators when on a viking is fascinating. However, I wonder whether a calcite crystal was also used by the Neolithic architects and builders of the temple at Newgrange, in Ireland, 5000 years ago. Visitors to Newgrange will be aware of the so-called roof-box, (I prefer Sun Window), which allows the dawn rays of the winter solstice sun to penetrate the huge construction and enter the inner chamber of Newgrange for about fifteen minutes on the four or so days on either side of the 21 December.

During his excavation and restoration of Newgrange during the late 1960's, Professor Michael O'Kelly found a large clear crystal in what he called the roof-box, but with scratch marks indicating there had originally been two such crystals. Though safe for five thousand years, in less than five, the one remaining crystal has been "lost." Nevertheless, I wonder whether these crystals were not quartz as most accept, but Iceland Spar which would have enabled the Neolithic priests, on cloudy days - common in Ireland - to determine the exact moment when the cloud covered winter solstice sun peaked over the far south eastern horizon and so launch whatever celebrations the inhabitants had deemed important. (Confusingly, both quartz and Icelandic Spar are called Sun Stones).

In this context, as the world at mid-winter to the Neolithic people was almost "dead", a ceremony to persuade their Great God, the Sun to symbolically impregnate the Earth Mother, (a visit to Newgrange will show the monument is a depiction of a womb in stone), and so fertilise the following year's crops, herds, schools of fish and most important, a new batch of Neolithic babies to keep the clans going.

Comments are welcome.
Chris

Is there any evidence or theory that transparent calcite may have been used by earlier cultures to help navigate (or to determine direction for some other purpose)?

Otis,
Check out: [en.wikipedia.org]

Rock Currier
Crystals not pistols.

The Wikipedia page only seems to mention use of Iceland spar by the Vikings and later groups. I'm interested in whether it was also used by earlier people.


Rock Currier Wrote:
-------------------------------------------------------
> Otis,
> Check out:
> [en.wikipedia.org]

According to Robert Ferguson (2009): The Hammer and the Cross, a new history of the Vikings", Viking navigation on a general basis was quite simple. When doing Europe they travelled near the coast, and no sofisticated navigation gear was required, when travelling to Iceland, The Faroes, Greenland etc, they sailed to certain landmarks along the Norwegian coast and took off into open sea from there. They used the height of the sun at certain times of the day to verify that they held the right latitude, and the time it took from to Norway to wherever to determin if they missed their target or not. Ferguson describes in detail the use of a "sun-shadow board" used for navigation. The description of it's use can be found in "Heimskringla", a contemporary Viking source, and it's use is also documented by finds in the Oseberg ship, and on Greenland. When considering the usefulness of such simplistic approach, please bear in mind that during the summer months, it is daylight almost around the clock at these latitudes, making navigation easier than further south.

Ferguson does mention the sunstone ( as well as other theories)": " A reference in a late and literary source describes the use of a sunstone, a mineral that occurs in Iceland with the property of polarizing light when held up in the direction of the sun. "Raudulfs thattr", a short story preserved in a manuscript from the early 14th century, describes the visit of the Norwegian King Olav Haraldson to the home of a rich farmer named Raudolf. Olav asked his host's son Sigurd if he had special talents, and the youth replied that indeed he did- he was able to tell the time day and night, even when no celestial body was visible. The king was interested and on the following day, which was overcast , he challenged the youth to demonstrate his skills. Once Sigurd had done so, Olav ordered a sun-stone to be brought out and held up in the general direction the sun was thought to be. In the story the light streams through the prism and Sigurd's remarkable talent is confirmed to the king's satisfaction." It should in this context be noted that King Olav Haraldson's reign lasted from 1025 to 1030, thus after the discovery of North America.

Ferguson summarizes his chapter on Viking navigation the following way: "To all such speculations we can only add the further presumption that efficient and safe long-distance navigation involved for the Vikings a knowledge of the major landmarks observabel on the longer voyages, of the direction and strength of currents at sea, of birds- particularily sea birds- and of their environments and habits of flight; of cloud formations; of the use of both day and night sky as an almanac;as well as a developed sensitivity of the subtleties of sea, sky and weather well in excess of anythiing we possess now.

Also relevant in this discussion is that the sagas claims that Iceland was discovered by accident when a bloke named Nadodd was blown off course on his way to the Faroes. Greenland was discovered by Eirik the Red, who was forced to find new land as he was outlawed in both Norway and Iceland due to a bad habit of killing his neighbours. North America was, according to the sagas, discovered in 985 by Bjarni Herjolfsson, who was sailing from Iceland towards Greenland, which he missed. Leiv Eiriksson, Eirik the Red's son deliberately sailed west from Greenland to find the land described by Bjarni, and when sailing west from Greenland, North America is rather hard to miss. Leiv Eriksson has been known as the Viking discoverer of North America. (i.e two of three great discoveries out west was made by accident).

I guess my point is that it seems that Leif Karlsson's theories on the use of a sun-stone is not a mainstream theory on Viking navigation, and that we should treat the sun-stone theory as one of many plausible theories and not as a proven fact.



Olav

My friend Norman Biggart has been researching the "sunstone" for years.

He believes that the "sunstone" was actually iolite / cordierite.

I have collected articles from various magazines including Lasers and Photonics and The Smithsonian which seem to support him.

I tend to think that the Vikings just used coastlines, luck, and maybe a lodestone.

Someone should conduct an experiment on this. Without a doubt the Vikings sailed the most fearsome boats on the oceans.

I think my ancestors were brought to Dublin, the Viking slaveport where some of my genes became combined with those of Greenland eskimos.

My other pet theory is that my eastern Mediterranean genes are from the Sarmatian expert horse boys of the Steppes who were kidnapped by the 3rd century Romans to defend Hadrian's Wall. Somehow relates to King Arthur's men.

Bart.

Further support for the Iceland Spar (calcite) theory was published this morning in USA Today - "Scientists: Vikings' 'mythical' sunstone found":

http://www.usatoday.com/story/news/world/2013/03/07/vikings-sunstone-crystal-myth/1970277/

(Yes, this is the popular newspaper "USA Today", but the original reference is March 6, 2013, Proceedings of the Royal Society, "The sixteenth century Alderney crystal: a calcite as an efficient reference optical compass?" by Albert Le Floch, Guy Ropars, Jacques Lucas, Steve Wright, Trevor Davenport, Michael Corfield, and Michael Harrisson.)



Edited 1 time(s). Last edit at 03/07/2013 09:06PM by Kelly Nash.

OK, let all of us who have an Iceland Spar calcite rhomb, a cordierite, andalusite - or even better a calcite dichroscope - step outside on a cloudy day at around noon. For those of us in the northern hemisphere the sun will then be due north of us, wherever we are, and due south for those in the southern hemisphere. The real keenies can also look up the angle of inclination of the sun above the horizon at noon for their latitude. So now we all know where the sun must be although we cannot see it.

Now, point your calcite rhomb/dichroscope at the clouds in the direction where you know the sun is. Twiddle your crystal(s) and watch for any indication of light polarisation.Will you see any? I'll bet you don't. I know that I don't. I offer to send a Viking-style helmet to any who can set out here a method for getting this to work by others.

It's third year school physics (or was, once upon a time) to know that sunlight is randomly polarised; there is no obvious reason why clouds of water droplets should act to rotate or filter the polarisation into a single plane. Indeed, one might expect that it would not do so.

There is only one condition attached to the offer of the helmet. Any lucky (clever) winner must take a pic of themselves wearing it and post is here One prize only. First proposed and successful solution (validated by me is the winner.

Whatever the outcome, I promise to advise the Royal Society of it, together with a copy of the picture of the winner. I can't promise that the offer of a Fellowship will follow though

Note that "Viking Helmets" did NOT have horns, I don't know where that myth came from..

The Vikigins were surely smart enough to have had a magnetic compass. And they surely knew more about coastlines than the modern British Navy.

Bart

In case any of you missed it, the premiere of "Vikings" was on the History Channel this past Sunday night. There is a scene on the show where they are examining a clear crystal, quite possibly the "Iceland Spar" everyone's talking about. They also showed a crude type of sundial navigation device?

Just a few notes. For most of the year, in the northern hemisphere, the sun will be due SOUTH of overhead at noon (and vice versa in the southern hemisphere). Also, sunlight in the sky is polarized - that is why photographers use a polarizer to darken the sky, as long as the view is roughly 90 degrees from the position of the sun in the sky. You can easily see this effect using a pair of polarizing sunglasses; look at a patch of sky about 90 degrees from the sun, and rotate the lens; the sky will alternately darken and lighten.