What about Zinc?
I found a pretty good post on zinc. The author references the price at 70c/lb, but it is currently 53-54c/lb.
I think the piece has some great information for research into zinc. The caution I have with any mining operation is demonstrated in the graphs. There are two infomine graphs, one with warehouse supply and the other with price. From 2000 to 2002 you can see an enormous growth in the excess zinc in the warehouse. It tripled in the 2 years and before it turned around it quadrupled. The point is that if you look at the graph you can really see how quickly the fundaments turned and that is the biggest caution with commodities. You need to look at where the commodity price is and where it can go.
Further, looking at the price graph for zinc screams bubble.
The current price for zinc is fairly low and looking at the graphs confirm this. The price bottomed around 35c/pound. My sense is today's 53-54 cents is relatively as low because the cost inputs into mining have gone up a lot. Technological advances to reduce costs have been having a declining effect and I think we are at the point that future cost savings from technology will be utterly marginal. So the capital invested in today's mines has a much higher break even point then in 2000. Indeed, some of these mines were built on bubbled prices for equipment, higher labour prices, etc. I suspect mines are struggling at today's price.
The other thing, look at the long term pricing of of zinc companies. Hudbay looks like it hit a low in 2005 of just under $2/shrare and it hit a high of around 30, a 1500% return with the right timing, and obviously an unsustainable return.
I don't think a bottom is in yet, going to 20% of the peak is still up 300% from the stock bottoms.