Poudretteite Locality: Mogok Township, Pyin-Oo-Lwin District, Mandalay Division, Burma (Myanmar) Size: 0.9 cm x 0.6 cm x 0.5 cm An exquisite gem crystal of an extreme rarity. Formerly known only from micros from Poudrette Quarry in Canada, a few small pockets of this material have now turned up in the Mogok Gem Tract. This is an extraordinary crystal for its form, good termination, and lavender color. In person, it is more gemmy. Joe Budd photos. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Poudretteite
An extremely rare potassium-boron ring silicate — a pink gem discovered in the 1960s at Mont Saint-Hilaire's Poudrette quarry.
Intro adapted from Wikipedia (CC BY-SA).
Poudretteite is an IMA-recognized mineral species in the silicate class, with the chemical formula KNa₂(B₃Si₁₂)O₃₀.
It crystallizes in the hexagonal crystal system (space group P6/mcc). It is a member of the Milarite structural group.
Key properties: Mohs hardness 5; specific gravity 2.51; White streak; Vitreous luster; refractive index 1.522; optically uniaxial.
IMA symbol Pou, IMA status: approved, named in 1986.
Found in marble xenoliths within nepheline syenite breccias in an intrusive alkalic gabbro-syenite complex.
It is found associated with Pectolite, apophyllite, aegirine.
The mineral was named to honor the Poudrette family, operators of the quarry where type material was discovered.