A highly fractionated, Li-F-Be-B-P-bearing granite pegmatite in calc-alkaline granite and hornfels.
Appears as a cupola over a PF leucogranite, displaying a non-symmetrical internal zonation with a complete sequence from a barren pegmatitic facies near the granite, to a highly evolved zone in the uppermost part of the body.
Al-rich micas show a continuous evolution from muscovitic to lepidolitic compositions from the leucogranite to the most evolved zone. Fe-rich micas range from Fe-biotite in the leucogranite and in the least evolved pegmatite zones, to an intermediate composition between zinnwaldite and trilithionite in the most evolved pegmatitic facies (Roda-Robles et al., 2006).
Refs.:
- Roda, E. et al. (1998). "The Fe-Mn phosphate associations from the Pinilla de Fermoselle pegmatite, Zamora, Spain: occurence of kryzhanovskite and natrodufrénite." European Journal of Mineralogy, 10(1).
- American Mineralogist (2005): 1887-1899.
- Roda-Robles, E., Pesquera, A., Gil-Crespo, P. P., Torres-Ruiz, J. & De Parseval, P. (2006): Mineralogy and geochemistry of micas from the Pinilla de Fermoselle pegmatite (Zamora, Spain). European Journal of Mineralogy, 18, 369-377.
