Jonesite

Jonesite is a mineral with the chemical formula Ba4(K,Na)2[Ti4Al2Si10O36]*6H2O.[4] This mineral is named after Francis Tucker Jones (1905–1993), who discovered the mineral while working as a Research Chemical Microscopist at Berkeley in CA.[5] Jonesite has diffraction symmetry of mmm, which implies an orthorhombic system with all three axes perpendicular to each other and the angles between each axis equal to 90 degrees.[6] In addition to symmetrical properties, Jonesite is a biaxial mineral with birefringence, which is a term to describe the difference between index of refraction.[7] Jonesite is anisotropic, meaning the speed of light changes through the mineral, so the mineral shows color when viewed in crossed polarized light under a microscope. The mineral also has medium relief, which is a measure of how well the mineral stands out when viewed under a microscope in plane polarized light.[8] In addition to being one of the rarest minerals in the Benitoite Gem mine located in California, Jonesite also is the first titanosilicate mineral with a porous double-layered crystal structure.[9] This discovery is important because titanosilicate frameworks have industrial uses in energy companies and are used in containing radioactive waste.[10]

Jonesite
General
CategoryInosilicates
Formula
(repeating unit)
Ba4(K,Na)2[Ti4Al2Si10O36]•6H2O
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupP21/m
Unit cella = 10.618, b = 25.918
c = 8.6945 [Å]; β = 127.633°; Z = 4
Identification
Formula mass914.93 g/mol
ColorColorless
Crystal habitBladed– Aggregation is thin blade-like crystals and Tabular– Dimensions thin in one direction
Cleavage{010} Distinct
FractureIrregular
Mohs scale hardness3–4
LusterVitreous
StreakWhite
DiaphaneityTransparent
Specific gravity3.21 g/cm3
Density3.25 g/cm3
Optical propertiesBiaxial (+), a=1.641, b=1.66, g=1.682, bire=0.0410
Refractive indexIndex: 1.64 to 1.68
Birefringenceδ = 0.041
PleochroismColorless
Other characteristicsHas medium relief and weak dispersion. Has fluorescent luminescence & white streak Year of Discovery:1977
References[1][2][3]

This article uses material from the Wikipedia article
 Metasyntactic variable, which is released under the 
Creative Commons
Attribution-ShareAlike 3.0 Unported License

Note

This article uses material from the Wikipedia article
 Metasyntactic variable, which is released under the 
Creative Commons
Attribution-ShareAlike 3.0 Unported License
.