Chemistry:Rodalquilarite

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Rodalquilarite
Rodalquilarite-130813.jpg
Rodalquilarite crystals from a cavity in alunite
General
CategoryTellurite mineral
Formula
(repeating unit)
H3Fe3+2(Te4+O3)4Cl
Strunz classification4.JL.05
Crystal systemTriclinic
Crystal classPinacoidal (1)
(same H-M symbol)
Space groupP1
Unit cella = 8.95 Å, b = 5.09 Å
c = 6.63 Å; α = 103.17°
β = 107.08°, γ = 77.87°; Z = 1
Identification
ColorEmerald- to grass-green
Crystal habitCrusts of stout crystals
CleavageOne good cleavage plane
TenacityVery brittle
Mohs scale hardness2 - 3
|re|er}}Greasy
StreakGreenish yellow
DiaphaneitySemitransparent
Specific gravity4.97 - 5.15
Optical propertiesBiaxial (-)
Refractive indexnα = 2.100 nγ = 2.200
Birefringenceδ = 0.100
2V angle38°
References[1][2][3]

Rodalquilarite is a rare iron tellurite chloride mineral with formula H3Fe3+2(Te4+O3)4Cl[1] or Fe2(TeO2OH)3(TeO3)Cl.[2] Rodalquilarite crystallizes in the triclinic system and typically occurs as stout green prisms and encrustations.

Discovery and occurrence

Green rodalquilarite crystals in a vug in pink alunite from Chile

Rodalquilarite was first described in 1968 for an occurrence in the Rodalquilar gold deposit of Almeria, Spain and was named for the discovery locality. It has also been reported from the Wendy open pit mine, El Indio-Tambo district, Coquimbo Region of Chile and the mines of Tombstone, Arizona.[1] It is found in the oxidized zone of tellurium-bearing gold deposits. It occurs associated with emmonsite, native gold, alunite, jarosite, quartz, native tellurium, mackayite and sonoraite.[1]

References

  1. 1.0 1.1 1.2 1.3 Rodalquilarite in the Handbook of Mineralogy
  2. 2.0 2.1 Rodalquilarite on Mindat.org
  3. Rodalquilarite data on Webmineral
  4. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine 85 (3): 291–320. doi:10.1180/mgm.2021.43. Bibcode2021MinM...85..291W.