In:
Bulletin Mineralogie Petrologie, Bulletin Mineralogie Petrologie, Vol. 28, No. 2 ( 2020), p. 359-363
Abstract:
A very rare bismuth sulphate, riomarinaite, was found in an old abandoned shaft on a Sn-W deposit Cínovec near Teplice, Northern Bohemia. This is first occurrence of this generally very rare mineral in the Czech Republic. Riomarinaite forms grey and blue acicular and columnar crystals up to 30 μm in size in association with native bismuth and bismuthinite. Riomarinaite is monoclinic, space group P21/n, the unit-cell parameters refined from X-ray powder diffraction data are: a 6.0091(19), b 13.328(5), c 6.483(3) Å, β 112.91(5)˚ and V 478.3(3) Å3. Chemical analyses of riomarinaite correspond to the empirical formula (Bi1.10Ca0.02)Σ1.12[(SO4)0.92(MoO4)0.08]Σ1.00(OH)1.33·H2O on the basis of S + Mo = 1 apfu. Raman bands connected with vibrations of (OH)-, H2O, (SO4)2- groups, Bi-O bonds and lattice modes were observed in the Raman spectrum of riomarinaite.
Type of Medium:
Online Resource
ISSN:
2570-7345
,
2570-7337
Language:
cs
Publisher:
Bulletin Mineralogie Petrologie
Publication Date:
2020