Gold bugs are a generally happy bunch this week. But they'd be a lot happier if precious metals mining stocks kept up with the metals themselves. Since early 2011 the largest gold miners have underperformed gold by about 40%, while the junior miners have done even worse (I'm talking to you, Great Basin).

Thanks to this divergence between the metals and the miners, it was possible to clearly understand the monetary destruction endemic in the developed world, conclude that gold and silver were the places to be, make a decisive bet on this thesis -- and still end up losing money.

There are two possible conclusions to draw from this: Either mining as a business has changed fundamentally and will be unprofitable forever - in which case we should just own physical metal and forget about paper proxies. Or the past couple of years were one of those inexplicable divergences from established relationships that produce huge gains when they snap back to normal.

The past month has offered a taste of what the second possibility might look like. The chart below shows that the big miners (represented by the GDX gold miner ETF, red line) have outperformed gold itself (the GLD bullion ETF, blue area) since July. But the two-year gap, like I said, is about 40%, so parity is still a long way off.

Now that the miners have some momentum, it wouldn't be surprising if they made up this ground in no time at all.

Gold miners (red line) versus Gold (blue) since mid-June