City sources predict the FTSE 100 will open down seven points from yesterday's close of 6,265, following a mixed picture in the US overnight. US markets ended the day very much mixed on Thursday, with the Dow Jones powering ahead in contrast to the NASDAQ, while the S&P 500 was flat, after hitting record highs earlier in the session. The Dow was boosted by better-than-expected jobless data, which saw initial weekly unemployment claims fall by 5,000 to the 330,000 mark (Consensus: 355,000).International economic announcements due out today include US new home sales and the German IFO business climate index, while here in the UK a preliminary GDP reading is expected at 09:30.In company news, Rolls Royce has completed the installation of the first MT30 gas turbines into the Royal Navy's new aircraft carrier HMS Queen Elizabeth. The company stated that two MT30s would be installed in each ship and would provide two thirds of the 109 megawatts needed to power the 65,000 tonne ships - enough energy to power a town the size of Swindon.Xstrata said Friday that the definitive estimate for the Las Bambas project in southern Peru is $5.2bn, reconfirming the updated estimate reported in August 20121 and the project's status as a world class, Tier 1 copper asset that will deliver "substantial value". The company said the project delivers robust financials, earning Xstrata's cost of capital at a life of mine flat copper price of $1.89 per pound. Strikes held back production of platinum and iron ore at Anglo American in the fourth quarter of 2012, though most other commodity classes delivered 'solid' increases in output. Iron ore output through its Kumba operations in South Africa dropped by 19% year-on-year due to illegal industrial action at the Sishen mine, which resulted in around five million tonnes of production being lost. This was partly offset by better-than-expected production at the Kolomela project.