This unheated cuprian tourmaline from Mozambique is half stable blue and half color changer (I call Laurellite). The top half of the picture is the Laurellite.
This smaller emerald cut is not pure and has somewhat muted colors, but is very exciting to me. You have to work with lighting to appreciate the special place this unheated cuprian tourmaline from Mozambique holds in the world of gemstones. Half of the gemstone remains blue whether is it illuminated by incandescent or natural light while the other half changes color from violet in natural light to blue in incandescent light. The half that has a reverse Alexandrite color change I call “Laurellite”. A similar stone that I sent to the GIA was confirmed to be a strong color changer and the first gem quality tourmaline from Mozambique, with copper as a significant chromophore (trace element that effects color), that had been analyzed by a gem laboratory and made public. When I heard about the finding of copper in the tourmaline on my birthday, before it was published in GIA’s Gem and Gemology magazine, I know it would be important for tourmaline and it was.
I will have much more to say about “Laurellite” on this site, but for now I will just post the picture I have of a unique bi-color in the collection. You will find the picture shows a “daylight” color distribution with the violet end toward top and I am unable to really show the color change with pictures.
It weighs 1.16 very important carats. This may help answer questions about why there is Laurellite.
Bruce
