The Al (Nb, Ta) Ti(in−2) substitution in titanite: the emergence of a new species?

Primary Sn-rich titianite in the Qitianling granite, Hunan Province, southern China: An important type of tin-bearing mineral and its implications for tin exploration

“…In contrast, titanite is a type of accessory mineral commonly present in granites, especially in calc-alkaline granites. Tin content is pronouncedly variable (SnO 2 =0.22 wt% [29] , 1.79 wt% [2] , and 7.40 wt% [8] ), difference being more than 2 orders of magnitude. In addition, tin occurs as trace element in some accessory minerals (e.g., ilmenite [10,22,30] ).…”

“…The hydrothermal alteration of the primary titanite and subsequent crystallization of cassiterite recorded a process of leaching and accumulation of tin in magmatic-hydrothermal evolution of the Sn-bearing granite. Thus, this titanite has important implications for tin exploration.Sn-bearing titanite, genetic mineralogy, implications for tin exploration, Qitianling, granite Tin deposits are genetically related to granitic rocks; thus, numerous studies have devoted to establishment of mineralogical, petrological, and geochemical criteria for tin-bearing granite [1][2][3][4][5] . In the literature, mica (mainly biotite) is generally treated as a type of diagnostic Sn-bearing mineral in granites.…”

“…Tin deposits are genetically related to granitic rocks; thus, numerous studies have devoted to establishment of mineralogical, petrological, and geochemical criteria for tin-bearing granite [1][2][3][4][5] . In the literature, mica (mainly biotite) is generally treated as a type of diagnostic Sn-bearing mineral in granites.…”

Titanite composition and SHRIMP U–Pb dating as indicators of post-magmatic tectono-thermal activity: Variscan I-type tonalites to granodiorites, the Western Carpathians

“…Titanite [previously sphene, CaTi(SiO 4 )O] together with rutile and ilmenite belongs to the most widespread titanium minerals of the Earth. There is a large variability of titanite presence in various lithologies from early Archean to recent, including (ultra)basic, intermediate, acid and alkaline magmatic suites including pegmatites, low-grade to UHP metamorphic rocks, as well as in some hydrothermal and sedimentary environments (e.g., Paul et al 1981;Bernau & Franz 1987;Nakada 1991;Gieré 1992;Russell et al 1994;Černý et al 1995;Bea 1996;Carswell et al 1996;Bouch et al 1997;Uher et al 1998;Castelli & Rubatto 2002;Chakhmouradian et al 2003;Broska et al 2007;Cempírek et al 2008;Xie et al 2010;Gao et al 2011;McLeod et al 2011;Chen et al 2016). The titanite structure (Speer & Gibbs 1976;Liferovich & Mitchell 2005, 2006 comprises three different cation sites plus five anion sites, and the general formula of the titanite-group minerals can be written as XYZO 4 W. The sites are inhabited by following cations: the tetrahedral Z site hosts Si 4+ (and possibly small amounts of Al 3+ , Ti 4+ , P 5+ , As 5+ , S 6+ , and vacancy), the octahedral Y site occupies Ti 4+ and various small to medium-sized cations (Mg 2+ , Fe 2+ , Fe 3+ , Al 3+ , Sc 3+ , Cr 3+ , Mn 3+ , As 3+ , Sb 3+ , V 3+ , V 4+ , Sn 4+ , Zr 4+ , Hf 4+ , Si 4+ , V 5+ , Nb 5+ , Ta 5+ , As 5+ , Sb 5+ , W 6+ ), the 7-coordinated X site polyhedra contain Ca 2+ and other mainly medium-to large-sized cations: Na + , K + , Fe 2+ , Mn 2+ , Sr 2+ , Ba 2+ , Pb 2+ , REE 3+ (La 3+ to Lu 3+ and Y 3+ ), Th 4+ , and U 4+ , whereas the anionic W site is occupied dominantly by O 2− ,…”

Hyperpotassic granulites from Blanský les (Moldanubian Zone, Bohemian Massif) revisited

“…Given the moderate to high Si, Ca and Fe contents (20.6 wt.% SiO 2 and 5-10 wt.% of both CaO and FeO) e.g. Černý et al 1995;Tiepolo et al 2002), the second prominent way of REE incorporation in titanites, seems to play a negligible role in this case. However, all these Ti modifications in UK5 exhibit heterogeneous surfaces with diffuse zoning on a small scale, which makes precise analyses and unambiguous identification very difficult.…”