Morganite and tourmaline. The pink to peachy variety of beryl…

Morganite and tourmaline.

The pink to peachy variety of beryl is coloured by trace impurities of manganese or caesium, was first discovered in Madagascar and named after the banker and mineral collector J.P. Morgan in 1910 by Tiffany’s famed gemmologist George Kunz (after whom Kunzite is named, but that’s a different tale). It grows in pegmatites, those crystallised rare element rich juices left over when granites stew. It can grow to quite large sizes, the US record holder was found in Maine, and weighed in at 23kg.
It varies in hue from lilac or violet, through pink to a delicious peachy orange. As for all coloured gems, saturation and tone of the hue are the most important quality factors, followed by clarity (freedom from inclusions) and beauty of cut. Since morganite’s hues are poorly saturated and light toned (ie quite pale and pastel), larger sized gems are needed to display the colour to its full beauty. They are usually quite high clarity, and have strong pleochroism, so must be cut in the right orientation to display the best colour.

Quality stones are rare, so rare in fact that they are comparatively cheap, since supply is not high enough for large volumes of mass market calibrated stones. It is often heat treated to remove a yellow component to the colour, and has been irradiated on occasion to induce colour. Common sources are Madagascar, Brazil, California, Afghanistan and Mozambique.

Loz

Specimen of morganite pierced by green tourmaline from Minas Gerais, Brazil, 13.8 x 8.0 x 11.7 cm

Image credit: Rob Lavinsky, iRocks.com.

http://gemstone.org/index.php?option=com_content&view=article&id=131%3Asapphire&catid=1%3Agem-by-gem&Itemid=14
http://www.mindat.org/min-2783.html
http://www.jtv.com/library/morganite.html
http://www.gia.edu/morganite-description
http://www.gia.edu/morganite-quality-factors
http://www.gemdat.org/gem-2783.html
http://www.gemsociety.org/info/gems/morganite.htm

Register, upload your video and earn revenue here https://rumble.com/register/rasrad/