TY  - JOUR
A1  - Ertl, Andreas
A1  - Giester, Gerald
A1  - Schüssler, Ulrich
A1  - Brätz, Helene
A1  - Okrusch, Martin
A1  - Tillmanns, Ekkehart
A1  - Bank, Hermann
T1  - Cu- and Mn-bearing tourmalines from Brazil and Mozambique: crystal structures, chemistry and correlations
JF  - Mineralogy and Petrology
N2  - Cu- and Mn-bearing tourmalines from Brazil and Mozambique were characterised chemically (EMPA and LA-ICP-MS) and by X-ray single-crystal structure refinement. All these samples are rich in Al, Li and F (fluor-elbaite) and contain significant amounts of CuO (up to ~1.8 wt%) and MnO (up to ~3.5 wt%). Structurally investigated samples show a pronounced positive correlation between the <Y-O> distances and the (Li + Mn\(^{2+}\) + Cu + Fe\(^{2+}\)) content (apfu) at this site with R\(^2\) = 0.90. An excellent negative correlation exists between the <Y-O> distances and the Al\(_2\)O\(_3\) content (R\(^2\) = 0.94). The samples at each locality generally show a strong negative correlation between the X-site vacancies and the (MnO + FeO) content. The Mn content in these tourmalines depends on the availability of Mn, on the formation temperature, as well as on stereochemical constraints. Because of a very weak correlation between MnO and CuO we believe that the Cu content in tourmaline is essentially dependent on the availability of Cu and on stereochemical constraints.
KW  - mineralogy
KW  - Brazil
KW  - Mozambique
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127296
VL  - 107
IS  - 2
ER  -