Dear Isogeochemists,
isotopic fractionation (D and O) of water of crystallisation of various
salts has been investigated very well (for instances: gypsum: Fontes &
Gonfiantini, 1967; mirabilite: Stewart, 1974; Sofer & Gat, 1972 from
aqueous salts). O-isotope effect of goethite and iron oxide (Fe2O3) is
reported by Yapp, GCA 1990.
However, does anybody know references about isotope fractionation (D and/or
O between "mother solution" and OH-water) in Fe-hydroxy-sulfato complexes
(i.e. jarosite [(Me2Fe+++6(OH)12(SO4)4] or similar minerals)? These
Fe-minerals are mostly stable only at pH < 3. Therefore, investigations
seem to be rare.
Thanks in advance.
Gerhard Strauch
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