Jenakite also referred to as Sahara Nuummite, is a variety of Nuummite which is a name that is unapproved a metamorphic orthoamphibole rock consisting primarily of two amphiboles – Anthophyllite and Gedrite. Nuummite was discovered in Greenland in 1982 and was only recognized to take place in Greenland until 2009 whenever a new source of gem-quality orthoamphibole that is iridescent found in the Sahara Desert of central Mauritania.
Several samples of this material that is brand new donated to GIA by Scott Davies of American-Thai Trading in Bangkok. This Nuummite from Mauritania has the iridescence that is certainly caused by blue to bluish green, although some stones show golden yellow and a little percentage really are a highly desirable blue that is pure. The latest Sahara Nuummite usually has a high density of needles, some of which can show a quite attractive blue color, unlike the first Greenland stones. The color that is blue said to be as a result of the presence of titanium. The stones take a polish that is great but cutting the material is challenging as the colorful iridescent needles only appear in very thin planes with a really narrow viewing orientation into the rough making yields low.
Raman spectra of the iridescent laths had been in line with Anthophyllite and Gedrite, that are orthorhombic people in the magnesium-iron-manganese-lithium group that is amphibole. Testing confirmed that the fancy needles are in reality the Anthophyllite that is amphibole primary element of Nuummite. The examples had RI measurements between 1.649 and 1.669, constant with the Raman recognition. Hydrostatic particular gravity was 2.98 ± 0.05, together with examples were inert to long- and UV radiation that is short-wave.
|Chemical Formula:||(Mg2)(Mg5)Si8O22(OH)2 + Ti|
|Magnesium Silicate Hydroxide + titanium|