"There are around 700,000 tonnes of copper sitting in the Shanghai bonded warehouse zone, give or take 100,000 tonnes. It's hard to say since this metal is not registered with any exchange and exists in the statistical twilight.
But it is, everyone agrees, the single largest concentration of refined copper anywhere in the world. It dwarfs the combined tonnage registered with the world's main three copper-trading exchanges; the London Metal Exchange, Comex in the United States and the Shanghai Futures Exchange."
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