(Sharecast News) - BHP on Tuesday said it had spent £45.6m to lift its stake in SolGold, which owns the Cascabel copper-gold project in Ecuador.The mining giant took an initial 6% stake in SolGold six weeks ago and now has 11.2%.Under the deal, BHP will buy 100m new shares in the company at 45p a 32% premium to the stock's 20 day average weighted closing price.