The paper presents the detailed mineralogical and petrographic study of spinel-bearing marbles at the Luc Yen deposit, North Vietnam. The LA-ICP-MS analysis of 74 spinel grains, combined with mineralogical data, allows us to discriminate them into fve types according to mineral assemblages and trace element geochemistry. Forty seven minerals are identifed as inclusions in spinel grains and 38 minerals are described at Luc Yen deposit for the frst time including leonardsenite, tintisite, manasseite, chalcoalumite, cobaltite and spherocobaltite. The mineral assemblages, trace element pattern, and specifc mineral inclusions indicate the involvement of hydrothermal fuids related to magma intrusions in the formation of, at least, two of fve spinel types at the deposit.

Figures 9. Tables 2. References 42.

Key words: spinel, mineralogy, marbles, Vietnam.

K.A. Kuksa, St. Petersburg State University, Universitetskaya nab., 7/9, St. Petersburg, 199034 katerina.kuksa@spbu.ru
 SOKOLOV Co. Ltd, ul. Gatchinskaya 11/A, 7N, St. Petersburg, 197136 Russia

O.Yu. Marakhovskaya, St. Petersburg State University, Universitetskaya nab., 7/9, St. Petersburg, 199034 ; 

G.A. Gussias, BalderGems Co., Pham van dong 66, Тo 8, Yen The, Luc Yen, YB 36000, Vietnam

W. Brownscombe, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom

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