Platinum miner Lonmin (LMI) is more accustomed to being at the bottom of the leader board after years of poor performance, safety issues and, more recently, violent labour strikes. It is therefore a surprise to see it lead the market with a 9% gain to 343.7p. Investors and analysts have applauded its first quarter production report. Stockbroker Panmure Gordon says the 185,000 ounces of concentrate produced in the three-month period is 29% more than it forecast. However, the lack of revised sales guidance (upwards) from the company would suggest that today's rally may be short lived. Panmure Gordon notes that labour-relation risks remain elevated. Investment bank Liberum says that Lonmin remains 'cash destructive' based on current production levels and metal prices.

Another serial disappointment joins the day's leader board. Oil services group Lamprell (LAM) jumped 5% to 128.25p after reassuring on trading following a string of profit warnings in 2012.

FTSE 250 pharmaceutical group BTG (BTG) advanced by 3% to 331.1p after saying that its results for the financial year to March 2013 would be at the top end of its £205 million to £215 million guidance. Its FTSE 100 sector peer, AstraZeneca (AZN), didn't fare as well, slipping 5.6% to £29.77 after saying that 2013 earnings will decline 'significantly more than revenue' this year as operating costs rise. The pharma giant is suffering from an erosion of business due to the expiry of patents on its drugs.

A bullish trading update is also the reason behind a strong turn from media giant British Sky Broadcasting (BSY), up 1.3% to 820.5p. Stockbroker Investec reckons the shares are worth 870p but flags up a potential short-term issue with costs as Sky plans to bring 700 engineers in-house.

Enterprise Inns (ETI) crashed 9% to 90p, ending a two-month rally where the shares nearly doubled in price. It has blamed 'exceptional trading conditions' for a 4.4% drop in like-for-like sales in the past 17 weeks. As well as the sector-wide problem of snow, Enterprise Inns has the problem of a supplier going into administration.

Among the small caps, mobile content retailer Mobile Streams (MOS:AIM) jumped 8% to 34.25p after saying that earnings in the second half of 2012 are expected to be 'significantly ahead' of the same period in 2011. This is being driven by growth in its mobile internet subscriber base in South America.

Sugar distributor-to-dairy ingredients specialist Real Good Food (RGD:AIM) hit a 12-month low after slumping 16% to 39.75p on a patchy third quarter trading update. The company implies that trading needs to be very good in the final three months of its financial year in order to meet forecasts.

Issue Date: 31 Jan 2013