Thailand, now one of the world's leading producers of fluorite, produced 395,070 metric tons in 1972, somewhat less than the record level of 427,498 tons the previous year. More than 155 deposits have been reported throughout the country; the main producing areas are in the northern and central regions.

Fissure veins and fault-fissure fillings of varied geometry are associated with hydrothermal mineralization

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genetically related to granitic igneous rocks. Regional geologic structure and the lithology of country rocks are the most important factors controlling localization and deposition of fluorite.

In some replacement fluorite deposits, both the fluorite and the country rocks have very similar visual characteristics. Microscopic study of thin sections can be of assistance in solving the problems of identification, quality control, and beneficiation of crude fluorite.

Experiments using geophysical methods for locating fluorite deposits have been introduced into exploration work. Gravimeter and magnetometer studies have been applied to the deposits, but they have been found useful only in broadly outlining local structures. Unfortunately, fluorite cannot be detected directly by these methods.

Until now, only easily worked surface fluorite has been mined at the several known deposits. Intensive exploration, underground mining, and sophisticated beneficiation facilities are needed to maintain high-production levels.

Estimated potential reserves of metallurgical-grade fluorite in Thailand are thought to exceed 11,500,000 metric tons.

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