Hostname: page-component-8448b6f56d-wq2xx Total loading time: 0 Render date: 2024-04-20T11:45:09.934Z Has data issue: false hasContentIssue false

Galeaclolusite, [Al6(AsO4)3(OH)9(H2O)4]⋅8H2O, a new bulachite-related mineral from Cap Garonne, France

Published online by Cambridge University Press:  04 December 2020

Ian E. Grey*
CSIRO Mineral Resources, Private Bag 10, Clayton South, Victoria3169, Australia
George Favreau
421 avenue Jean Monnet, 13090Aix-en-Provence, France
Stuart J. Mills
Geosciences, Museums Victoria, GPO Box 666, Melbourne, Victoria3001, Australia
W. Gus Mumme
CSIRO Mineral Resources, Private Bag 10, Clayton South, Victoria3169, Australia
Catherine Bougerol
Université Grenoble Alpes and CNRS, Institut Néel, 38000, Grenoble, France
Helen E.A. Brand
Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria3168, Australia
Anthony R. Kampf
Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA90007, USA
Colin M. MacRae
CSIRO Mineral Resources, Private Bag 10, Clayton South, Victoria3169, Australia
Finlay Shanks
School of Chemistry, Monash University, Clayton, Victoria3800, Australia.
*Author for correspondence: Ian E. Grey, Email:


Galeaclolusite, [Al6(AsO4)3(OH)9(H2O)4]⋅8H2O, is a new secondary hydrated aluminium arsenate mineral from Cap Garonne, Var, France. It forms crusts and spheroids of white fibres up to 50 μm long by 0.4 μm wide and only 0.1 μm thick. The fibres are elongated along [001] and flattened on (100). The calculated density is 2.27 g⋅cm–3. Optically, galeaclolusite is biaxial with α = 1.550(5), β not determined, γ = 1.570(5) (white light) and partial orientation: Z = c (fibre axis). Electron microprobe analyses coupled with crystal structure refinement results gives an empirical formula based on 33 O atoms of Al5.72Si0.08As2.88O33H34.12. Galeaclolusite is orthorhombic, Pnma, with a = 19.855(4), b = 17.6933(11), c = 7.7799(5) Å, V = 2733.0(7) Å3 and Z = 4. The crystal structure of galeaclolusite was established from its close relationship to bulachite and refined using synchrotron powder X-ray diffraction data. It is based on heteropolyhedral layers, parallel to (100), of composition Al6(AsO4)3(OH)9(H2O)4 and with H-bonded H2O between the layers. The layers contain [001] spiral chains of edge-shared octahedra, decorated with corner-connected AsO4 tetrahedra, that are the same as in the mineral liskeardite.

Copyright © The Author(s), 2020. Published by Cambridge University Press on behalf of The Mineralogical Society of Great Britain and Ireland

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)


Associate Editor: Oleg I Siidra


Favreau, G. and Galea-Clolus, V. (2014) Cap Garonne. Association Française de Microminéralogie, Carry-le-Rouet, France.Google Scholar
Frau, F. and Da Pelo, S. (2001) Bulachite, a rare aluminium arsenate from Sardinia, Italy: the second world occurrence. Neues Jahrbuch für Mineralogie, Monatshafte, 2001, 1826.Google Scholar
Gagné, O.C. and Hawthorne, F.C. (2015) Comprehensive derivation of bond-valence parameters for ion pairs involving oxygen. Acta Crystallographica, B71, 562578.Google Scholar
Grey, I.E., Mumme, W.G., MacRae, C.M., Caradoc-Davies, T., Price, J.R., Rumsey, M.S. and Mills, S.J. (2013) Chiral edge-shared octahedral chains in liskeardite, [(Al,Fe)32(AsO4)18(OH)42(H2O)22]⋅52H2O, an open framework mineral with a pharmacoalumite-related structure. Mineralogical Magazine, 77, 31253135.CrossRefGoogle Scholar
Grey, I.E., Mumme, W.G., Price, J.R., Mills, S.J., MacRae, C.M. and Favreau, G. (2014) Ba-Cu ordering in bariopharmacoalumite-Q2a2b2c from Cap Garonne, France. Mineralogical Magazine, 78, 851860.CrossRefGoogle Scholar
Grey, I.E., Brand, H.E.A. and Betterton, J. (2016) Dehydration phase transitions in new aluminium arsenate minerals from the Penberthy Croft mine, Cornwall, UK. Mineralogical Magazine, 80, 12051217.CrossRefGoogle Scholar
Grey, I.E., Favreau, G., Mills, S.J., Mumme, W.G., Bougerol, C., Brand, H.E.A., Kampf, A.R., MacRae, C.M. and Shanks, F. (2020a) Galeaclolusite, IMA 2020-052, in: CNMNC Newsletter 58, Mineralogical Magazine, 84, Scholar
Grey, I.E., Yoruk, E., Kodjikian, S., Klein, H., Bougerol, C., Brand, H.E.A., Bordet, P., Mumme, W.G., Favreau, G. and Mills, S.J. (2020b) Bulachite, [Al6(AsO4)3(OH)9(H2O)4]⋅2H2O from Cap Garonne, France: Crystal structure and formation from a higher hydrate. Mineralogical Magazine, 84, 608615.CrossRefGoogle Scholar
Libowitzky, E. (1999) Correlation of O-H stretching frequencies and O–H⋅⋅⋅O hydrogen bond lengths in minerals. Monatsche fur Chemie, 130, 10471059.CrossRefGoogle Scholar
Mandarino, J.A. (2007) The Gladstone-Dale compatibility of minerals and its use for selecting mineral species for further study. The Canadian Mineralogist, 45, 13071324.CrossRefGoogle Scholar
Mills, S.J., Christy, A.G., Schnyder, C., Favreau, G. and Price, J.R. (2014) The crystal structure of camerolaite and structural variation in the cyanotrichite family of merotypes. Mineralogical Magazine, 78, 15271552.CrossRefGoogle Scholar
Mills, S.J., Christy, A.G., Colombo, F. and Price, J.R. (2015) The crystal structure of cyanotrichite. Mineralogical Magazine, 79, 321335.CrossRefGoogle Scholar
Mills, S.J., Christy, A.G., Favreau, G. and Galea-Clolus, V. (2017) Multidimensional structural variation in the cyanotrichite family of merotypes: camerolaite-3b-F-1. Acta Crystallographica, B73, 950955.Google Scholar
Mills, S.J., Christy, A.G. and Favreau, G. (2018) The crystal structure of ceruleite, CuAl4[AsO4]2(OH)8(H2O)4, from Cap Garonne, France. Mineralogical Magazine, 82, 181187.CrossRefGoogle Scholar
Mills, S.J., Missen, O.P. and Favreau, G. (2019) The crystal structure of Ni-rich gordaite-thérèsemagnanite from Cap Garonne, France. Mineralogical Magazine, 83, 459463.CrossRefGoogle Scholar
Mills, S.J., Kolitsch, U., Favreau, G., Birch, W.D., Galea-Clolus, V. and Henrich, J.M. (2020) Gobelinite, the Co analogue of ktenasite from Cap Garonne, France, and Eisenzecher Zug, Germany. European Journal of Mineralogy, 32, 637644.CrossRefGoogle Scholar
Myeni, S.C.B., Traina, S.J., Waychunas, G.A. and Logan, T.J. (1998) Experimental and theoretical vibrational spectroscopic evaluation of arsenate coordination in aqueous solutions, solids and at mineral–water interfaces. Geochimica Cosmochimica Acta, 62, 32853300.CrossRefGoogle Scholar
Petříček, V., Dušek, M. and Palatinus, L. (2014) Crystallographic Computing System JANA2006: General features. Zeitschrift für Kristalloraphie, 229, 345352.Google Scholar
Pouchou, J. (1993) PAP – X-ray microanalysis of stratified specimens. Analytical Chimica Acta, 283, 8197.CrossRefGoogle Scholar
Plášil, J., Petříček, V., Mills, S. J., Favreau, G. and Galea-Clolus, V. (2018) Zippeite from Cap Garonne, France: an example of reticular twinning. Zeitschrift für Kristallographie – Crystalline Materials, 233, 861865.CrossRefGoogle Scholar
Sarp, H. and Chiappero, P. J. (1992) Deloryite, Cu4(UO2)(MoO4)2(OH)6, a new mineral from the Cap Garonne mine near Le Pradet, Var, France. Neues Jahrbuch für Mineralogie, Monatshefte, 1992, 5864.Google Scholar
Schafer, D., Donn, M., Atteia, O., MacRae, C., Raven, M., Pejcic, B. and Prommer, H. (2018) Fluoride and phosphate release from carbonate-rich fluorapatite during managed aquifer recharge. Journal of Hydrology, 562, 809820.CrossRefGoogle Scholar
Walenta, K. (1983) Bulachit, ein neues Aluminiumarsenatmineral von Neubulach im nördlichen Schwarzwald. Aufschluss, 34, 445451.Google Scholar
Supplementary material: File

Grey et al. supplementary material

Grey et al. supplementary material

Download Grey et al. supplementary material(File)
File 876.2 KB