Spectrolite

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 iridescence of spectrum colours from blue to red. It is often cut as a lapidary cabochon and used as a gemstone.

Additional recommended knowledge

How to ensure accurate weighing results every day?

Safe Weighing Range Ensures Accurate Results

What is the Correct Way to Check Repeatability in Balances?

Spectrolite was discovered by the Finnish 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, Madagascar 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.