National University of Science and Technology—MISIS, Moscow, Russia:

Yushina T. I., Head of department, Associate Professor, Candidate of Engineering Sciences, yuti62@mail.ru
Dumov A. M., Associate Professor, Candidate of Engineering Sciences
Nguyen Van Chon, Post-Graduate Student
Nguyen Thu Thuy, Post-Graduate Student

Sericite is a silicate mineral, a finely disperse and partly hydrated variety of muscovite. It is widely applied in many areas of engineering and production, and has a high economic value. Sericite has been produced and used in the world for a few hundred years. In Vietnam, a new-discovered sericite deposit holds commercial quality reserves. This article presents the studies into the mineral composition of sericite ore from Ha Tinh deposit using a set of the modern analytical techniques, which prove efficiency of the commercial-level production and processing of this ore. The integrated studies into material constitution of Ha Tinh sericite ore show the uniform structure of sericite and insignificant content of unwanted impurities. The size of sericite particles markedly differs from the size of other minerals in the initial ore. The content of quartz gradually increases with increasing size of ore particles, while the content of sericite gradually grows with decreasing size of particles. In particularly, in very fine particles (size less than 10 μm), the content of sericite is higher than in the initial ore by 2 times and reaches 70%, while the content of quartz is 4 times less than in the initial ore. Impurities feature nonuniform distribution and occur in some mineral grains such as apatite Ca₅(PO₄O)₃, iron oxides and binding particles of solid solutions. During ore processing, impurities can be separated to waste, and it is possible to produce a marketable product in the form of a high quality sericite powder which meets the application standards of the porcelain, ceramic, resin and other industries. Thus, Hà Tĩnh sericite ore can be converted into valued products to be used in many various industries.

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