The prices of both metals were down this holiday-shortened (Labor Day in the US) week, especially on Friday. The decline corresponded to a spike in interest rates. Of course everyone watched the action of the stock market on Friday. Whatever the proximate cause, the root is credit. When borrowing to buy assets does not work, then selling assets to repay debt is required. It could be companies who bought their own shares, it could be European banks. It could be leveraged investors speculators in…