TAFFEITE MUSGRAVITE

Natural Rough Gemstone
Diaphaneity : Transparent to Translucent


TAFFEITE
(/ˈtɑːf aɪt/; BeMgAl4O8) is a mineral named after its discoverer Richard Taaffe (1898–1967), who found the first sample, a cut and polished gem, in October 1945 in a jeweler's shop in Dublin, Ireland. As such, it is the only gemstone originally identified from a cut stone. Most of the gem pieces, prior to Taaffe, had been misidentified as spinel. For many years afterward, it was known only in a few samples, and it remains one of the rarest gemstone minerals in the world. Magnesiotaaffeite-2N'2S (Mg 3 Al 8 BeO 16 )

General
Category : Oxide Minerals

Formula : (repeating unit)BeMgAl4O8​​​Symbol IMATf [ 1 ]

Strunz Classification : 4.FC.25

Crystal System : Hexagonal

Crystal Class : Dihexagonal Pyramid (6mm)

Trigonal Dipyramidal ( 3 m)
(magnesiotaaffeite-6N'3S and ferrotaaffeite-6N'3S)

Color Identification :
Colorless, grayish purple, purple red, red, brown to red, greenish, light green, pinkish purple, light purple, greenish blue

Crystal Habit : Prismatic alluvial grains, massive

Twinning :
With reflection on (0001)

Cleavage : Imperfect/adequate/none

Fracture : Conchoid

Mohs scale hardness : 8–8.5

Luster : Vitreous

Lines : White

Opaqueness : Transparent to translucent

Specific gravity : 3.60–3.61

Optical properties : UniaxialRefractive indexnω = 1.722, nε = 1.777
Birefringenceδ value = 0.055PleochroismWeakReferences[2] [3]

Since 2002, the International Mineralogical Association's approved name for taaffeite as a mineral is magnesiotaaffeite-2N'2S.