Did Vikings Navigate to North America Using Stones?

A mythical mineral given to the Vikings by Norse gods could have its basis in reality.

Vikings sailing across the North Atlantic hundreds of years ago might have made it to North America by navigating with a stone that can detect where the sun is shining from in cloudy weather. Iceland spar, a transparent form of the mineral calcite, could be the fabled "sunstone" found in Norse myths that would guide explorers by revealing where the sun is when held up to the sky. Experiments performed with the mineral found that it can accurately point out the sun's location within a degree, even if the sun is beyond the horizon. We'll let the Daily Mail explain just how this works:

Researchers found that if you put a dot on top of the crystal and look through it from below, two dots will appear due to the double refraction of the Iceland spar.

Using this, they could pinpoint the sun by rotating the crystal until both sides of the double image are of equal intensity.

At that angle, the upward-facing surface indicates the direction of the sun, according to the scientists led by Dr Guy Ropars.

A precision of a few degrees can be reached even under dark twilight conditions, so the Vikings would have been able to determine with precision the direction of the hidden Sun.

Got that? Ropars said the discovery of a large chunk of Iceland spar in a shipwreck from 1592 leads him to think that it was an ancient navigation device used before the advent of the compass in the 13th century. All we know is that the image of a viking warrior holding a crystal aloft as he traverses the stormy North Atlantic is one of the most bad-ass historical images we've ever dreamt up. All the better if it led to the European discovery of Canada.