Torshab Mine Stone

STANISLAV K. FILATOV
Department of Crystallography, St. Petersburg University, University Emb. 7/9, St. Petersburg 199034, Russia
LIDIYA P. VERGASOVA
Institute of Volcanology of the Russian Academy of Sciences, Piyp Ave. 9, Petropavlovsk-Kamchatskii 683006, Russia
MARINA G. GORSKAYA AND SERGEY V. KRIVOVICHEV§
Department of Crystallography, St. Petersburg University, University Emb. 7/9, St. Petersburg 199034, Russia
PETER C. BURNS
Department of Civil Engineering and Geological Sciences, University of Notre Dame, 156 Fitzpatrick Hall,
Notre Dame, Indiana 46556-0767, U.S.A.
VLADIMIR V. ANANIEV
Institute of Volcanology of the Russian Academy of Sciences, Piyp Ave. 9, Petropavlovsk-Kamchatskii 683006, Russia
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INTRODUCTION
Bradaczekite is a sodium copper arsenate,
NaCu4(AsO4)3, recently discovered within a fumarole
in the North Breach of the Great fissure Tolbachik eruption
(GFTE) in the Kamchatka Peninsula, Russia. The
mineral is named in honor of Hans Bradaczek (b. 1940),
crystallographer at the Free University of Berlin. The
type specimen is deposited in the Mining Museum,
Mining Institute, St. Petersburg, Russia. The mineral
and mineral name have been approved by the Commission
on New Minerals and Mineral Names, IMA (case
2000–002). Bradaczekite has a synthetic analogue
(Pertlik 1987). Our purpose is to document the physical
and chemical attributes of this new species.

X-RAY CRYSTALLOGRAPHY
Unit-cell parameters of bradaczekite were initially
determined using a Weissenberg camera and were further
refined by crystal-structure analysis. The mineral
is monoclinic, space group C2/c, a 12.051(1), b
12.434(1), c 7.2662(7) Å,  117.942(1)°, V 961.8(2) Å3,
and Z = 4. X-ray powder-diffraction data were obtained
using CuK
radiation (DRON–2 diffractometer, Ge internal
standard). The powder pattern, together with intensities
calculated from the crystal structure, are
given in Table 2. The crystal-structure refinement of
bradaczekite and its detailed description will be given
elsewhere.
FIG.





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