So I've been looking at some 25 year charts on commodities...

So I've been looking at some 25 year charts on commodities (http://www.indexmundi.com/commodities/), and it looks as if a number of commodities are trading very near all time lows. I believe in real terms commodities don't tend to change in value, so it pays to look at prices in inflation adjusted terms.
So looking at zinc as a case study (the inflation adjusted value in todays prices shown in brackets)
Oct 1983 $857.60 ($1763)
Nov 1985 $597.45 ($1136) - historical low
Oct 2002 $755.09 ($865) - recent low
Oct 2008 $1100 - at $0.50/lb

The story is about the same for nickel, though nickel has some new low cost production mines forecast that could see cost of production drop substantially.

Zinc is trading around all time lows, if the economy goes to hell it mostly means zinc production will be pared back, I don't see the value deteriorating significantly lower (is this fair to say?). Mines aren't going to continue producing at heavy losses.

So the question is, is it a fairly safe bet to take a long position in zinc at these prices? Nothing is as simple as it seems, so I wanted to hear what others might feel are risks associated with this strategy. It just seems very low downside risk, with decent level of upside potential.

Also can anyone recommend a trading broker for commodity futures in Australia (for base metals)? Is this even possible for small investors?