There's a lot of things in the share price as if the good news is going to continue.

Rio wants assets on a world class basis, and the sale is a reflection of the quality and scale of assets it wants. It has a track record of selling assets and getting good prices at the top of the market.

It's obviously exposed to the resources area, which is a growth area at the moment. It's perceived as a quality company with good growth potential.

For demand, China is the key factor.

The Chinese want to diversify their supplies and with the small miners they can get equity stakes that they can't get from the bigger ones like Rio Tinto. If they can get in early, they may be able to lock in supplies at good prices.

Manufacturing is probably in a steady downtrend, and when you get cheap imports, it is a recipe for a bit of margin contraction.