16.3 Placer deposits
About 80 percent of the world's tin deposits occur not as primary lodes, but as unconsolidated secondary or placer deposits in river beds and valleys or on the sea floor. The largest concentration of both onshore and offshore placers is in the extensive tin belt of South-East Asia, which stretches from China in the north, through Thailand, Burma and Malaysia, to the islands of Indonesia in the south.
Compared with commercially viable deposits of copper, lead, zinc, nickel and bauxite, tin deposits are generally small. Further, tin is almost always found closely allied to the granite from which it originates.
16.3 Placer deposits
About 80 percent of the world's tin deposits occur not as primary lodes, but as unconsolidated secondary or placer deposits in river beds and valleys or on the sea floor. The largest concentration of both onshore and offshore placers is in the extensive tin belt of South-East Asia, which stretches from China in the north, through Thailand, Burma and Malaysia, to the islands of Indonesia in the south.
Compared with commercially viable deposits of copper, lead, zinc, nickel and bauxite, tin deposits are generally small. Further, tin is almost always found closely allied to the granite from which it originates.
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