Wesselsite, SrCu[Si4O10], a further new gillespite-group mineral from the Kalahari Manganese Field, South Africa.
- Author(s)
- Gerald Giester, Branko Rieck
- Abstract
Wesselsite, SrCu[Si4O10], is a new mineral species from the Wessels mine, Kalahari Manganese Field, South Africa, and it belongs to the gillespite group. Wesselsite is tetragonal, space group P4/ncc; the unit cell parameters, refined from Gandolfi film data, are a = 7.366(1), c = 15.574(3) .ANG., V = 845.01 .ANG.3. The strongest lines are (dobs/Ions/hkl) (7.79/35/002), (4.33/20.112), (3.89/20/004), (3.44/40/104), (3.33/100/202), (3.12/55/114), (3.03/50/212), (2.68/25/204), (2.61/30/220) and (2.32/30/116). Wesselsite is assocd. with hennomartinite, embedded in a matrix of sugilite, xonotlite, quartz and pectolite. Microprobe analyses of 111 samples show that it is the end-member of a solid soln. series with effenbergerite, BaCu[Si4O10], with substitutions of Sr by Ba up to 50 mol.%. Wesselsite forms tiny subhedral plates in sizes not exceeding 50 x 50 x 5 µm, arranged in clusters of up to 200 mm. It shows a perfect cleavage parallel to {001}, has blue color, white to light blue streak, and is uniaxial neg. with n-omega = 1.630(2), ne = 1.590(5), strongly pleochroic from blue (omega) to pale blue (epsilon). The calcd. d. is 3.32 g/cm3; the measured d. is 3.2(1) g/cm3.
- Organisation(s)
- Department of Mineralogy and Crystallography
- Journal
- Mineralogical Magazine
- Volume
- 60
- Pages
- 795 - 798
- No. of pages
- 4
- ISSN
- 0026-461X
- DOI
- https://doi.org/10.1180/minmag.1996.060.402.09
- Publication date
- 1996
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105113 Crystallography, 104011 Materials chemistry, 105116 Mineralogy
- Keywords
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/wesselsite-srcusi4o10-a-further-new-gillespitegroup-mineral-from-the-kalahari-manganese-field-south-africa(97876696-8493-45d4-830c-1542f9e5e08b).html