Thailand's waters are every bit as bountiful as its fields and forests. According to the Fisheries Department, a fleet of more than 16,000 powered vessels plying the waters off the country's roughly 3,000 km. coastline approximately 2.6 million tons of marine products a year. Freshwater fish abound. Besides the many varieties which breed naturally in rivers, lakes and streams, there are those raised by rice farmers in their flooded paddy fields and harvested together with the rice. In addition, the Fisheries Department is vigorously promoting freshwater aquaculture by farmers with large ponds.
Freshwater prawns are also plentiful.
Mineral reserves in Thailand are rich and varied, with 1993 exports earning of 3,980 million baht. Tin, for centuries the biggest moneymaker among Thai minerals, remains so today, with the country ranking fourth behind Brazil, Indonesia, and Malaysia. Gemstones, among them the legendary Siamese rubies and sapphires, have also long been mined in Thailand. Thailand's coloured gems market is one of the world's largest. Export of gems and jewelry in 1993 ranked third among exports, earning 40,921 million baht.