Like GLD with, the authorized market participants for SLV add silver in response to more buying pressure than selling pressure and vice versa. Clearly there has been positive money flow for gold and silver ETFs over the past week.
Since April 26 iShares Silver Trust (SLV), the largest physical metal-backed silver exchange traded fund has seen a remarkable negative money flow. In that short period selling pressure for the shares of SLV overwhelmed buying.
Panic flight to cash, margin calls and irrational fear knocks gold and especially silver lower on the paper-contract dominated spot cash markets while the real physical bullion markets get even tighter. The divergence between pricing in the paper futures market and the physical bullion market reaches extreme levels for silver as the gold:silver ratio goes over 80:1.
Following the U.S. Fed and Treasury Department's blatant intervention raid on gold and silver to bolster the U.S. dollar, the few large U.S. banks that hammered the futures markets with an avalanche of short futures sales have covered most of the short contracts in gold, but not silver, yet.