I wrapped a natural optical calcite crystal with wide silver aluminum wire. I made it with the points up and down in a diamond shape. Like most Iceland spar specimens, this one has rainbow prisms. It also has some interesting inclusions. Comes with a 24 inch 925 silver chain.
Iceland spar is clear variety of calcite originally found in Iceland. It was often used in experiments involving light polarization, as it is well known for its double refraction qualities. It easily divides into rhomboid shapes. Some historians have speculated that it is the original sun stone mentioned in medieval texts (solarsteinn), that Vikings used to tell the direction of the sun on overcast days.
Iceland spar is a good cleansing stone and can amplify environmental energy. It is also restorative and helps to accelerate psychic development and spiritual growth. It provides insight in negative situations and aids in clarification during confusing emotional states.
Available in my store: maryannkaydesigns.com/products…
Experts have long argued that Vikings knew how to use blocks of light-fracturing crystal to locate the Sun through dense clouds, but archaeologists have never found hard proof, and doubts remained as to exactly what kind of material it might be.
An international team of researchers led by Guy Ropars of the University of Rennes in Brittany, marshalling experimental and theoretical evidence, says they have the answer. Vikings, they argue, used transparent calcite crystal -- also known as Iceland spar -- to fix the true bearing of the Sun, to within a single degree of accuracy. This naturally occurring stone has the capacity to "depolarize" light, filtering and fracturing it along different axes, the researchers explained.
Here's how it works: "If you put a dot on top of the crystal and look through it from below, two dots will appear. Then you rotate the crystal until the two points have exactly the same intensity or darkness. At that angle, the upward-facing surface indicates the direction of the Sun," Ropars explained by phone. "A precision of a few degrees can be reached even under dark twilight conditions. Vikings would have been able to determine with precision the direction of the hidden Sun." He added, "The human eye has a fine-tuned capacity to distinguish between shades of contrast, and thus is able to see when the two spots are truly identical."