Labradorite is a stone that which shows adularescence (a white or bluish light seen when turned). This optical effect is so unique to labradorite that it has been termed "labradorescence". It's the result of diffraction of light in the layers of rock.
Labradorite was first found in the city of Labrador, Canada in the 1770's, thus the name. When viewed at certain angles, labradorite exhibits such captivating color that has led to Inuit legends stating that the Northern Lights shone down on the shores of Labrador and were captured inside these colorful stones. Is that poetic or what? By wearing this necklace you'd be adorned by the Northern Lights. ; )