The case for Comex explained in one chart http://i54.tinypic.com/sotzds.png
If silver stockpiles continue to be withdrawn at the current annual growth rate, Comex could be drained by the end of 2012. As for the Treasury and U.S. Mint holdings, the last audit in 2010 showed roughly 7 million ounces in deep storage.
There isn't much silver left.
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