Wairakite

Wairakite
Wairakite from Azerbaijan
General
CategoryZeolite minerals
Formula
(repeating unit)
Ca8(Al16Si32O96)•16H2O
IMA symbolWrk[1]
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[2][3]

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.[4][5] The first finds were in hydrothermally altered rhyolitic tuffs, ignimbrites and volcaniclastic rocks.[5] 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.[6]

References

[edit]
  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ Mindat
  3. ^ Mineralienatlas
  4. ^ Szostak, Rosemarie (1992), Handbook of molecular sieves, Springer, p. 482, ISBN 0-442-31899-5
  5. ^ a b Steiner, Alfred (1955), "Wairakite, the calcium analogue of analcime, a new zeolite mineral" (PDF), Mineralogical Magazine and Journal of the Mineralogical Society, 30 (230): 691–698, Bibcode:1955MinM...30..691S, doi:10.1180/minmag.1955.030.230.02, retrieved 2011-09-08
  6. ^ Liou, J. G. (1970), "Synthesis and stability relations of wairakite, CaAl2 Si4 O12·2H2O", Contributions to Mineralogy and Petrology, 27 (4): 259–282, Bibcode:1970CoMP...27..259L, doi:10.1007/BF00389814, S2CID 128557961