Spectrolite is a hard and rare variety of labradorite feldspar. Spectrolite has a Mohs hardness between 6 and 6.5 and a specific gravity of 2.69 to 2.70. The variety is noted for its intense play of colors showing various irridescences of spectrum colours from blue to red. It is commonly cut as a lapidary cabochon and used as a gemstone.

Spectrolite was discovered by the Finns during WWII when building a defense line in Ylämaa in southeast Finland. After the war, spectrolite was mined in small quantities. This small supply made it more valuable. Although labradorite is found in Labrador, Norway, Madagaskar and Russia in addition to Finland, the Finnish stones have been mined and marketed under the name Spectrolite, which was given by a professor Aarne Laitakari.

External links

• Information from Kiviseppä Ky

spectrolite: www.ylamaa.fi/english/index.htm

Silicate minerals | Gemstones

Spektroliitti