...Juraj Majzlan; Edgar Dachs; Artur Benisek Abstract Copiapite-group minerals are common products of weathering of sulfides, especially pyrite and pyrrhotite. They have a general formula A Fe 3+ 4 (SO 4 ) 6 (OH) 2 ·20H 2 O and all crystallize in the triclinic crystal system (space group P...

... octahedrally coordinated A sites. Our synthetic and natural copiapite samples can be divided into two large groups based on the orientation of the structural fragments. One group comprises copiapite phases where A = Al 3+ , Fe 2+ or Fe 3+ and we designate it as the structural type AL. The other group consists...

...., by solutions of linear simultaneous equations. Proportions in the X and R positions of the structural formula are assumed 1:4 on the basis of substitution which at the same time serves as a check on obtained solutions. Identified species of the copiapite group include aluminocopiapite, copiapite...

... solutions on the ambient minerals and rocks. Minerals of the copiapite group display a remarkably wide range of compositional variations ( Atencio et al. 1996 ). The general formula of these minerals is A Fe 3+ 4 (SO 4 ) 6 (OH) 2 (H 2 O) 20 , where A = Fe 2+ (copiapite sensu stricto ), Mg 2...

..., pickeringite, alunogen, epsomite, hexahydrite, a smectite-group phase, galena, sphalerite, and trace calcite. Rhomboclase and copiapite were identified by XRD in only one <2 μm sample. The water-soluble sulfates are not pure end-member phases: pickeringite and epsomite contain Zn (Zn:Mg atomic ratio from 1...

... occurrence, other iron sulfates were identified, including alum-(K), “copiapite”, fibroferrite, halotrichite, melanterite, römerite, and voltaite. Volaschioite occurs as radial aggregates of bladed crystals, up to 100 μm in length and less than 5 μm across. The color is yellowish orange with an orange...

... of (Fe 0.68 Mg 0.24 Cu 0.05 Zn 0.03 ) ∑1.00 SO 4 .7H 2 O. Melanterite was also found in mixtures with the Fe 2+ salt minerals rozenite and szomolnokite and aluminocopiapite, an Al-rich end-member of the copiapite group. All salt minerals which include melanterite contained a greater mass of Cu to Zn...

... ·22H 2 O     apjohnite Mn 2+ Al 2 (SO 4 ) 4 ·22H 2 O     wupatkiite Co 2+ Al 2 (SO 4 ) 4 ·22H 2 O     dietrichite ZnAl 2 (SO 4 ) 4 ·22H 2 O     bilinite Fe 2+ Fe 2 3+ (SO 4 ) 4 ·22H 2 O     redingtonite Fe 2+ (Cr,Al) 2 (SO 4 ) 4 ·22H 2 O Copiapite Group (OH-bearing...

... to sequester Cu and Zn is well known ( Frau 2000 , Jambor et al. 2000 , Hammarstrom et al. 2005 ). Structural substitutions of several heavy metals have been also documented in epsomite-, hexahydrite- and chalcanthite-group minerals ( Jambor et al. 2000 ). The ability of copiapite-group minerals...

... by the same doublet with δ = 0.41 mm/s and Δ = 1.14–1.21 mm/s. Botryogen is also related to and in the same Strunz classification group as copiapite; recall from discussion above that copiapite also has a doublet with parameters of δ = 0.42–0.43 mm/s and Δ = 0.77–0.80 mm/s. In addition to the doublets with Δ...

... Nicolas Meisser. The new mineral was found in a sandstone matrix and is associated with chalcanthite, copiapite, ferrinatrite, gypsum, johannite and another new Na-bearing uranyl sulfate, belakovskiite (IMA2013-075). Meisserite is a secondary mineral formed by the post-mining weathering of uraninite...

..., and hexahydrite, but other ammonium minerals (salammoniac, mascagnite, clairite, boussingaultite, efremovite, koktaite, mohrite, ammoniojarosite, godovikovite, letovicite) as well as native sulfur, millosevichite, alunogen, metavoltine, voltaite, gypsum, anhydrite, halotrichite, butlerite, jarosite, and copiapite...

... ( Demartin et al. 2010b ). Structural changes related to a variation in composition at the octahedral sites have also been observed for other sulfates of ferric iron, such as those in the copiapite group ( Majzlan & Michallik 2007 ), and can also be expected in other open structures...

..., secondary mineral occurring in a sulfate assemblage with anhydrite, botryogen, chalcanthite, copiapite, halotrichite, hexahydrite, hydroniumjarosite, pyrite, römerite, rozenite and szomolnokite. Lavender-coloured crystals up to several mm across form dense intergrowths. More rarely crystals occur as drusy...