Not much longer. Physical keeps disappearing from the shelves at many dealers. Finally, in order to avoid a Wizard of OZ situation (look, there's a man behind the curtain!) the black boxes are forced to stop. The ETFs give them plenty of ammo for manipulation of physical markets, unfortunately.

The powers that be are fighting a rearguard action, and in order to have the ability to manipulate in the future, they have to stop before it's too obvious, before prices get too cheap that it triggers even more buying.

There's more money than ever, and the miners and developers are being discouraged from producing with artificially low prices.

This is one of the reasons I like Silver Wheaton, btw. They have upside to the metals, but suffer less from inflation than any of the real mining companies.