kigel,
For most of the second half of last year the miners tended to do their own thing on a day to day basis. There were days when they did the exact opposite of the main indeces. All I would suggest is that over a, let's say, two week period, any position you open will usually get back to your opening price. But over that fortnight it could go £5-£6 against you before showing a profit. I can vouch for that cos I've been there.That's the volatility of RIO, and miners in general. Not much help I suppose.