The short answer is almost nothing in the real world.
The longer answer is where silver gets interesting.
The price most people follow is driven by paper silver, mainly contracts. These contracts are rarely settled with physical metal. They are opened, closed, or rolled. Because of that, prices can move very fast without a single ounce changing hands.
Futures markets set prices, but they do not clear physical imbalances. When leverage dominates, prices can diverge from physical reality temporarily.
