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Lead-antimony sulfosalts from Tuscany (Italy). XVI. Carducciite, (AgSb)Pb6(As,Sb)8S20, a new Sb-rich derivative of rathite from the Pollone mine, Valdicastello Carducci: occurrence and crystal structure

Published online by Cambridge University Press:  05 July 2018

Cristian Biagioni ,
Paolo Orlandi ,
Yves Moëlo  and
Luca Bindi
Cristian Biagioni*
Affiliation:
Dipartimento di Scienze della Terra, Universita` di Pisa, Via S. Maria 53, I-56126 Pisa, Italy
Paolo Orlandi
Affiliation:
Dipartimento di Scienze della Terra, Universita` di Pisa, Via S. Maria 53, I-56126 Pisa, Italy
Yves Moëlo
Affiliation:
Institut des Matériaux Jean Rouxel, UMR 6502, CNRS, Université de Nantes, 2, rue de la Houssiniére, 44 322 Nantes Cedex 3, France
Luca Bindi
Affiliation:
Dipartimento di Scienze della Terra, Universita` di Firenze, Via G. La Pira 4, I-50121 Florence, Italy
*
* E-mail: [email protected]
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Abstract

The new mineral species carducciite, (AgSb)Pb6(As,Sb)8S20, has been discovered in the baryte-pyrite- (Pb-Ag-Zn) deposit of the Pollone mine, near Valdicastello Carducci, Apuan Alps, Tuscany, Italy. It occurs as black metallic prismatic crystals, up to 0.5 mm long, associated with pyrite and sterryite. Its Vickers hardness (VHN10) is 61 kg/mm2 (range: 52–66), corresponding to a Mohs hardness of ~2½–3. In reflected light, carducciite is dark grey in colour, moderately bireflectant; internal reflections are very weak and deep red in colour. Reflectance percentages for the four COM wavelengths [Rmin, Rmax (%) (λ)] are: 35.8, 40.8 (471.1 nm), 33.7, 39.0 (548.3 nm), 32.7, 37.6 (586.6 nm) and 30.4, 35.1 (652.3 nm). Electron microprobe analysis gives (wt.% – mean of six analyses): Ag 3.55(12), Tl 0.13(3), Pb 41.90(42), Sb 17.79(19), As 12.41(14), S 22.10(17), total 97.9(6). On the basis of ΣMe = 16 a.p.f.u., the chemical formula is Ag0.96Tl0.02Pb5.91As4.84Sb4.27S20.14. The main diffraction lines, corresponding to multiple hkl indices, are (relative visual intensity): 3.689 (s), 3.416 (s), 3.125 (s), 2.989 (s), 2.894 (s), 2.753 (vs), 2.250 (s). The crystal-structure study gives a monoclinic unit cell, space group P21/c, with a 8.4909(3), b 8.0227(3), c 25.3957(9) Å, β 100.382(2)°, V 1701.63(11) Å3, Z = 2. The crystal structure has been solved and refined to a final R1 = 0.063 on the basis of 4137 observed reflections. It can be described within the framework of the sartorite homologous series, as formed by chemically twinned layers of the dufrénoysite type. The simplified idealized structural formula, based on 20 sulfur atoms, can ideally be written as (AgSb)Pb6(As,Sb)Σ=8S20. Carducciite is an (Ag,Sb)-rich homeotype of dufrénoysite, stabilized by the complete coupled substitution 2 Pb2+ = Ag+ + Sb3+ on a specific site of the crystal structure. Together with barikaite, it belongs to the rathite sub-group of P21/c homeotypes of dufrénoysite, of which the crystal chemistry is discussed. The distribution of Ag, coupled with As or Sb on specific sites, appears to be the main criterion for the distinction between the three species of this sub-group.

Keywords

carducciitenew mineralrathitesulfosaltleadsilverantimonyarseniccrystal structurePollone mineApuan AlpsTuscanyItaly
Type
Research Article
Information
Mineralogical Magazine , Volume 78 , Issue 7 , December 2014 , pp. 1775 - 1793
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2014

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References

Baumhauer, H. (1896) Ueber den Rathit, ein neues mineral aus dem Binnenthaler Dolomit. Zeitschrift für Kristallographie, 26, 593–602.Google Scholar
Berlepsch, P., Armbruster, T. and Topa, D. (2002) Structural and chemical variations in rathite, Pb8Pb4–x(Tl2As2)x(Ag2As2)As16S40: modulations of a parent structure. Zeitschrift für Kristallographie, 217, 581–590.Google Scholar
Berlepsch, P., Armbruster, T., Makovicky, E. and Topa, D. (2003) Another step toward understanding the true nature of sartorite: determination and refinement of a ninefold superstructure. American Mineralogist, 88, 450–461.CrossRefGoogle Scholar
Biagioni, C., Orlandi, P., Moëlo, Y., Pardini, S. and Passarino, G. (2012) Sterryite e parasterryite. I solfosali aciculari di piombo e argento della miniera del Pollone (Pietrasanta, Lucca). Rivista Mineralogica Italiana, 2/2012, 76–91.Google Scholar
Biagioni, C., Moëlo, Y., Orlandi, P., Stanley, C.J. and Evain, M. (2013a) Meerschautite, IMA 2013-061. CNMNC Newsletter No. 17, October 2013, page 3004. Mineralogical Magazine, 77, 2997–3005.Google Scholar
Biagioni, C., Orlandi, P. and Moëlo, Y. (2013b) Carducciite, IMA 2013-006. CNMNC Newsletter No. 16, August 2013, page 2702. Mineralogical Magazine, 77, 2695–3709.Google Scholar
Brese, N.E. and O’Keeffe, M. (1991) Bond-valence parameters for solids. Acta Crystallographica, B47, 192–197.CrossRefGoogle Scholar
Bruker AXS Inc. (2004) APEX 2. Bruker Advanced Xray Solutions, Madison, Wisconsin, USA.Google Scholar
Cannon, R., Hensel, H. and Raber, T. (2008) Der Reckibach-Dolomi t im Binntal, Schweiz: Mineralbestand und Neufunde. Lapis, 33, 20–28.Google Scholar
Carmignani, L., Dessau, G. and Duchi, G. (1976) I giacimenti a barite, pirite ed ossidi di ferro delle Alpi Apuane. Studio minerogenetico e strutturale. Bollettino della Societa` Geologica Italiana, 95, 1009–1061.Google Scholar
Costagliola, P., Benvenuti, M., Lattanzi, P. and Tanelli, G. (1998) Metamorphogenic barite-pyrite (Pb-Zn- Ag) veins at Pollone, Apuane Alps, Tuscany: vein geometry, geothermobarometry, fluid inclusions and geochemistry. Mineralogy and Petrology, 62, 29–60.CrossRefGoogle Scholar
Hatert, F. and Burke, E.A.J. (2008) The IMA-CNMNC dominant-constituent rule revisited and extended. The Canadian Mineralogist, 46, 717–728.CrossRefGoogle Scholar
Jambor, J.L. (1967) New lead sulfantimonides from Madoc, Ontario – Part 1. The Canadian Mineralogist, 9, 7–24.Google Scholar
Kraus, W. and Nolze, G. (1996) POWDER CELL – a program for the representation and manipulation of crystal structures and calculation of the resulting Xray powder patterns. Journal of Applied Crystallography, 29, 301–303.CrossRefGoogle Scholar
Laroussi, A., Moëlo, Y., Ohnenstetter, D. and Ginderow, D. (1989) Argent et thallium dans les sulfosels de la série de la sartorite (Gisement de Lengenbach, vallée de Binn, Suisse). Comptes Rendus de l’Académie des Sciences, Paris, 308 (Série II), 927–933.Google Scholar
Lima-de-Faria, J., Hellner, E., Liebau, F., Makovicky, E. and Parthé, E. (1990) Nomenclature of inorganic structure types. Report of the IUCr Commission on Crystallographic Nomenclature Subcommittee on the Nomenclature of Inorganic Structure Types. Acta Crystallographica, A46, 1–11.Google Scholar
Makovicky, E. (1985) The building principles and classification of sulphosalts based on the SnS archetype. Fortschritte der Mineralogie, 63, 45–89.Google Scholar
Makovicky, E. and Topa, D. (2013) The crystal structure of barikaite. Mineralogical Magazine, 77, 3093–3104.CrossRefGoogle Scholar
Marumo, F. and Nowacki, W. (1965) The crystal structure of rathite-I. Zeitschrift für Kristallographie, 122, 433–456.CrossRefGoogle Scholar
Marumo, F. and Nowacki, W. (1967) The crystal structure of dufrenoysite, Pb16As16S40. Zeitschrift für Kristallographie, 124, 409–419.CrossRefGoogle Scholar
Moëlo, Y., Makovicky, E., Mozgova, N.N., Jambor, J.L., Cook, N., Pring., A., Paar, W.H., Nickel, E.H., Graeser, S., Karup-Møller, S., Balić-Žunić, T., Mumme, W.G., Vurro, F., Topa, D., Bindi, L., Bente, K. and Shimizu, M. (2008) Sulfosalt systematics: a review. Report of the sulfosalt subcommittee of the IMA Commission on Ore Mineralogy. European Journal of Mineralogy, 20, 7–46.CrossRefGoogle Scholar
Moëlo, Y., Orlandi, P., Guillot-Deudon, C., Biagioni, C., Paar, W. and Evain, M. (2011) Lead-antimony sulfosalts from Tuscany (Italy). XI. The new mineral species parasterryite, Ag4Pb20(Sb14.5As9.5)S24S58, and associated sterryite, Cu(Ag,Cu)3Pb19(Sb,As)S22 (As–As)S56, from the Pollone mine, Tuscany, Italy. The Canadian Mineralogist, 49, 623–638.CrossRefGoogle Scholar
Moëlo, Y., Guillot-Deudon, C., Evain, M., Orlandi, P. and Biagioni, C. (2012) Comparative modular analysis of two complex sulfosalt structures: sterryite, Cu(Ag,Cu)3Pb19(Sb,As)22(As-As)S56, and parasterryite, Ag4Pb20(Sb,As)24S58. Acta Crystallographica, B68, 480–492.CrossRefGoogle Scholar
Nowacki, W. and Bahezre, C. (1963) Die bestimmung der chemischen Zusammensetzung einiger Sulfosalze aus dem Lengenbach (Binnatal, Kt. Wallis) mit Hilfe der elektronischen Mikrosonde. Schweizerische Mineralogische und Petrographische Mitteilungen, 43, 407–411.Google Scholar
Orlandi, P., Biagioni, C., Bonaccorsi, E., Moëlo, Y. and Paar, W.H. (2012) Lead-antimony sulfosalts from Tuscany (Italy). XII. Boscardinite , TlPb4(Sb7As2)S9S18, a new mineral species from the Monte Arsiccio mine: occurrence and crystal structure. The Canadian Mineralogist, 50, 235–251.CrossRefGoogle Scholar
Orlandi, P., Biagioni, C., Moëlo, Y., Bonaccorsi, E. and Paar, W.H. (2013) Lead-antimony sulfosalts from Tuscany (Italy). XIII. Protochabourné ite, ~Tl2Pb(Sb9-8As1-2)S10S17, from the Monte Arsiccio mine: occurrence, crystal structure and relationship with chabournéite. The Canadian Mineralogist, 51, 475–494.CrossRefGoogle Scholar
Pandeli, E., Bagnoli, P. and Negri, M. (2004) The Fornovolasco schists of the Apuan Alps (Northern Tuscany, Italy): a new hypothesis for their stratigraphic setting. Bollettino della Societa` Geologica Italiana, 123, 53–66.Google Scholar
Pring, A. (2001) The crystal chemistry of the sartorite group minerals from Lengenbach, Binntal, Switzerland – a HRTEM study. Schweizerische Mineralogische und Petrographische Mitteilungen, 81, 69–87.Google Scholar
Sawada, H., Kawada, I., Hellner, E. and Tokonami, M. (1987) The crystal structure of senandorite (andorite VI): PbAgSb3S6. Zeitschrift für Kristallographie, 180, 141–150.CrossRefGoogle Scholar
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64, 112–122.CrossRefGoogle Scholar
Topa, D., Makovicky, E., Tajedin, H., Putz, H. and Zagler , G. (2013) Barikaite , Pb1 0Ag3 (Sb8As11)S19S40, a new member of the sartorite homologous series. Mineralogical Magazine, 77, 3039–3046.CrossRefGoogle Scholar
Wilson, A.J.C. (editor) (1992) International Tables for Crystallography Volume C: Mathematical, Physical and Chemical Tables. Kluwer Academic Publishers, Dordrecht, The Netherlands.Google Scholar