Alunite supergroup: recommended nomenclature

Abstract

Minamiite has been discredited and renamed natroalunite-2c to show a double unit-cell structure and natroalunite can be designated as natroalunite-1c to show a single unit-cell structure. Kintoreite can be designated as kintoreite-1c to show the same single unit-cell structure, and IMA 1993-039 is a new superstructure of kintoreite and can be designated as kintoreite-2c to show a double unit-cell structure. Beaverite has been renamed beaverite-(Cu). The Zn-bearing beaverite of Sato et al. (2008) has been named “beaverite-(Zn)”, but data for the mineralhave not been approved by the CNMNC. Orpheite has been discredited as P-rich hinsdalite. Proposal 07-D was approved by the CNMNC.

Ce(III) and Ce(IV) (re)distribution and fractionation in a laterite profile from Madagascar: Insights from in situ XANES spectroscopy at the Ce LIII-edge

“…Typically, REE-aluminophosphates of the alunite supergroup are zoned and show complex variations of compositions. The alunite supergroup has a DG 3 (TX 4 ) 2 X' 6 general structural formula (e.g., Bayliss et al, 2010) with a large compositional flexibility which allows Ce(III) and Ce(IV) to be accommodated in the D site. Indeed, the Ce oxidation state depends on the microstructural positions of the REE-phosphate in the Bhorizon of the Madagascar laterite (X Ce(III) -XANES = 34-100%, Table 3).…”

Single-crystal X-ray diffraction study of synthetic sodium–hydronium jarosite

“…A range of cations can be incorporated into jarosite group minerals such as A = Na, K, Ag, Tl, H 3 O, NH 4 , Pb, B = Fe 3+ and T = S (e.g. Stoffregen et al 2000;Bayliss et al 2010). Jarosite senso stricto [K jarosite, KFe 3 (SO 4 ) 2 (OH) 6 ] and Na jarosite [NaFe 3 (SO 4 ) 2 (OH) 6 ] are the most common jarosite species observed in nature (e.g.…”

Geoenvironmental Characterisation of Heap Leach Materials at Abandoned Mines: Croydon Au-Mines, QLD, Australia

“…Whilst identification of these phases is relatively uncommon, they are reported as oxidation products forming in such environments, the majority of which are from the alunite supergroup [35,36]. For example, carminite is an alteration product of arsenopyrite forms in the oxidized zone of lead-bearing deposits, and is commonly associated with beudantite and anglesite [37].…”