Labradorite has got is name due to the Canadian peninsula of Labrador where it was discovered in 1770. Labradorite is plagioclase feldspar and shows play of color in lustrous metallic tints, often blue and green. This play of color is caused by the interferences of light on twinned lamellae. A ray of light entering a layer and being refracted back and forth by deeper layers causes the resulting color effect. This refracted ray is slowed by the extra travel through the layers and mixes with other rays to produce a light ray coming out that have a different wavelength than when it went in.
Labradorite is found in Labrador (Canada), Finland, the former USSR and Norway.
Chemical Composition: Sodium Calcium Aluminium Silicate
Crystal Structure: Triclinic
Specific Gravity: 2.70
Refractive Index: 1.56-1.57
Colors: White and dark gray to grayish black with play of color.
Labradorite feldspar is considered to be one of the birthstones for the month of November, which covers two zodiac signs: Scorpio (October 23 To November 21) and Sagittarius (November 21 To December 21).