Wairakite

Wairakite
Wairakite from Azerbaijan
General
CategoryTectosilicate minerals, zeolite group
FormulaCa8(Al16Si32O96)•16H2O
IMA symbolWrk
Strunz classification9.GB.05
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupI2/a
Unit cella = 13.69 Å, b = 13.64 Å
c = 13.56 Å; β = 90.51°; Z = 8
Identification
Colorcolorless to white
Lustervitreous, dull
Streakwhite
Diaphaneitytransparent, translucent
References

Wairakite is a zeolite mineral with an analcime structure but containing a calcium ion. The chemical composition is Ca8(Al16Si32O96)•16H2O. It is named for the location of its discovery in Wairakei, North Island, New Zealand, by Czechoslovakian mineralogist Alfred Steiner in 1955. The first finds were in hydrothermally altered rhyolitic tuffs, ignimbrites and volcaniclastic rocks. The mineral has since been found in metamorphic rocks and in geothermal areas. It was most likely first successfully synthesized in a laboratory in 1970.