A lovely colour flash in this cabochon. size is 18.6 x 19.18 x 3.11 mm at widest points. video here. https://www.youtube.com/watch?v=tK2r3NWAmzU
This is genuine Spectrolite from Ylamaa in Finland handcut by myself.
A plagioclase feldspar in the same family as Labradorite and moonstone, displaying with intense reds, oranges and yellows as well as blues and greens, Spectrolite is found only in Finland. Spectrolite was discovered quite by accident in 1940 during the Second World War, when stone was being quarried Finland's eastern border for the purpose of making antitank obstacles, which makes it a more recent discovery than the well-known Labradorite from Canada and Madagascar. I find it divine that this light came into the world at such a dark time. Spectrolite reminds us of this as it goes dark and then, flashes it's light at us. Spectrolite is a very high grade of dark based labradorite found only in Finland. If the stone is from Madagascar or Labrador it is NOT Spectrolite and is not a semi precious gem. The name "Spectrolite" is a trade name given to this material by the Finns, and only this material can truly be called Spectrolite.