Matt,of late IGO's share price has been dependent on the success...

Matt,
of late IGO's share price has been dependent on the success or otherwise of the Tropicana development - rather than production levels or commodity prices. As the project has moved closer to production the share price has consolidated. For the near term, it will probably be driven by announcements regarding the ramp up of production, and to the gold price.
Having watched IGO's share price rise and fall over the years - I think the short term movements (daily & weekly) are driven more by positioning of large shareholders rather than commodity prices, resource upgrades and the like. The turnover of shares is often quite small and if an institution decides that it wants to increase or decrease their holding then the share price will move quite significantly. For instance, an order to buy or sell 100,000 shares would move IGO's share price significantly.
Over longer periods of time its commodity prices, production levels, cost controls and the like that drive the price (and influence the large shareholders to increase or decrease their holdings).
Anyway, for what its worth - that's my view.
Sirecho