The recent finds of fluor-cannilloite from "Yuang Yang (Yueng Yang), Wenshan, Yunnan Province, China" are really from this locality.
Yuang Yang is in fact a small city in Yunnan Province where mineral dealers frequently offer Vietnamese specimens.
There are numerous quarries spread along a 12 km line in this area, all generally labelled "Luc Yen", athough some should probably be renamed.
NOTE: Some of the "paragasites" from here may be fluor-cannilloites
(see http://www.mindat.org/mesg-7-69925.html). Nonetheless, Hauzenberger et al. (2005) report intense green pargasite in association with red spinel from Luc Yen. This pargasite has been confirmed by EPMA and single-crystal XRD.
References:
- Eugeni Bareche (2007) An Phu, Luc Yen, Vietnam. Revista de Minerales (Barcelona), 2007/2, 26-29.
- Tamagnini, F. (2007). Tormaline policrome in Vietnam. Un nuovo ritrovamento nei pressi di Luc Yen. Rivista Mineralogica Italiana, 31 (2), 104-107.
- Hauzenberger, Ch.A., Walter, F., Hofmeister, W., Phan Tien, D. & Kienzl, N. (2005): Mineralogical, petrological and crystallographic investigations of two amphiboles from ruby and spinel bearing marbles, Luc Yen, Province Yen Bai, Vietnam. In: Hofmeister, W. et al. (ed): Proceedings of the third international workschop on gem-materials and modern analytical methods. Hanoi, Vietnam. 3-8.
- www.ruby-sapphire.com/vietnamese_rubies.htm
