Home » Rock Directory

Labradorite

A variety of plagioclase feldspar found in igneous rocks and characterized by brilliant colors in some specimens.

Type of feldspar mineral in the plagioclase series that is often valued as a gemstone and as ornamental material for its red, blue, or green iridescence. The mineral is usually gray or brown to black and need not be iridescent. Labradorite is named for its occurrence on the coast of Labrador, Canada.

A plagioclase feldspar with composition range Ab50An50 to Ab30An70 (Ab = NaAlSi₃O₈; An = CaAl2Si₂O₈). In some labradorite samples brilliant colors, much like those seen in oil films on water, result from the interference of light reflected at successive lamellar interfaces.

A type of feldspar with an uninteresting background color but displaying an iridescence which gives the stones its value. The background color is a dark smoke gray, but when light strikes it in a particular direction, it displays striking rainbow-colored reflections (peacock blue, coppery red or dusky gold) known as labradorescence.

Labradorite is thought by some to symbolize the moon and the sun and has, in fact, been found to be a constituent of moon rock. Feldspar, and therefore, labradorite, assists one to progress from old ways, encouraging unconventional and exciting new methods to attain one’s goals. Labradorite can also assist one to handle changes, promoting strength and perseverance. It has been known as the matriarch of the subconscious mind, facilitating the transformation of intuition into intellectual thoughts. It is said to be helpful in the treatment of disorders of the brain, to stimulate mental acuity and to reduce anxiety and stress. It can assist in digestion, regulation and metabolism and has been used to clarify the eyes. Labradorite is Saturday’s gemstone.

Material Notes:
Two cleavage directions. Weathering end product(s): Kaolinite illite. Occurrence: Igneous rocks metamorphic. All feldspars are good indicators of the rock freshness.

Although labradorite is best known for its common (actually, not all that common, rather it is the exception) form with a bluish, silvery, or multi-colored "schiller" iridescence, not all labradorite has that appearance. Most labradorite is gray, without the schiller, but some gem-quality labradorite is transparent pale yellow, with or without an iridescence. The Plush, Oregon labradorite "sunstone" is either clear yellow, orange, or red, and some of it has an iridescence which is due to microscopic inclusions of copper--something very unusual among feldspars, which was a surprise when its discovery was announced. Pale yellow gemmy labradorite is also found in New Mexico and Mexico.

[ Close ]