By Chisom Ibemere
Labradorite is known as a calcium-enriched feldspar mineral which is first identified in Labrador, Canada. It shows a Schiller effects also called an iridescent effect.
Labradorite has 50 and 70 anorthite percentage and known to be intermediate to calcic member of the plagioclase series. It has a specific gravity between 2.68 to 2.72 and a white streak similar to silicates. The refractive index ranges from 1.559 to 1.573 and twinning is common. It has a triclinic crystal system with three directions cleavage.
Labradorite shows a clear, white or gray, block shaped grains in common mafic igneous rocks like basalt and gabbro and also in anorthosites.
Labradorite is found in places like Canada, Poland, Norway, Finland and most locations worldwide, with notable distribution in Madagascar, China, Australia, Slovakia and the United States.
Labradorite is a feldspar variety that is more common to basalt and gabbros. It is found in mafic igneous rocks. It can be seen also in metamorphic amphibolites and as a detrital component of some sediments. Its common mineral associates in igneous rocks are olivine, pyroxenes, amphiboles and magnetite. It displays an effect called iridescent optical effect (or schiller) which is known as labradorescence.
Labradorite has been a highly sought-after stone since it was discovered for jewellery production. It can also be used in other applications aside from jewelry making such as; in the production of glass, road construction and ceramic manufacturing.
