Why did the shopping centre and fruit juice carton cross the road? To invest in a Russian gold miner. Investors today were scratching their heads as to why two Russian investors have snapped up more than a third of Russian miner Polyus Gold (PGIL), given their backgrounds in vastly-different industries. Market talk says there is logic in the transaction.

Russian billionaire Mikhail Prokhorov's Onexim group has sold its 37.8% stake in Polyus for $3.6 billion. The holding has been taken up by two parties. Retail specialist Zelimkhan Mutsoev has paid $1.77 billion for 18.5% of the Russian gold miner; and 19.3% has gone to fruit juice magnate Gavriil Yushvaev for $1.85 billion.

Market gossip suggests they are the latest Russian 'minigarchs' to help Suleiman Kerimov - 40% owner of Polyus - sideline takeover rules, this time paving the way for a merger with Polymetal (POLY). If Mutsoev and Yushvaev had been found to be a 'concert party', working together, then they would have been forced to make a mandatory takeover offer for Polyus. Following the announcement regarding the change in ownership, Polyus jumped 2.1% to 223.5p and Polymetal advanced 2.7% to 971.5p.

A disappointing set of full-year results have dragged Millennium & Copthorne (MLC) down 2.6% to 553p. Profits were below expectations and there?s only a marginal rise in the dividend. As we discuss here, a weak start to 2013 is out of kilter to other quoted hoteliers.

A profit warning has dragged Vianet (VNET:AIM) down 15.5% to 98.5p. The small cap, which helps landlords to monitor beer volumes and spot when bar staff are giving away free drinks, blames increased investment in the US, delays to new contracts and pressure in the leisure sector. The board insists that cash generation remains strong and that it will pay a 5.7p total dividend for the year to 31 March 2013, putting the shares on a 5.8% yield.

Electronics small cap Datong (DTE:AIM) jumped 30.8% to 51p after putting itself up for sale. The £7 million cap says it has already been approached by a potential bidder, so it wants to see what other interest there is in the market.

After a wobbly start since being spun out of Sylvania Platinum (SLP:AIM) in August 2012, South Africa-based explorer Ironveld (IRON:AIM) has finally found market support and has been on a massive rally since the start of 2013, rising 166% to 5.52p. Today's news of a 40% resource upgrade fuels the share price momentum.

Hospital operator Circle (CIRC:AIM) improved 7% to 69p after saying full-year results to be reported on 18 April would beat forecasts. The group has £38 million of cash and has received a funding offer to develop a site in Manchester.

Analyst Charles Weston of house broker Numis talks up the stock, saying: ?We believe that Circle continues to offer an interesting opportunity for investors to gain exposure to an emerging independent hospital provider which is well placed to capitalise on the evolving nature of healthcare in the UK.? Yet analysts at Investec want a greater insight into management?s strategy, saying: ?All in all good progress, but we still need more clarity on the future direction before opining on valuation.?

Shares in oil explorer Mediterranean Oil & Gas (MOG:AIM) advanced 8.2% to 11.5p after the Italian Ministry of Environment revealed it had ruled in favour of the group?s environmental impact study for its offshore Ombrina Mare discovery - a significant step in the development of the find. Broker Liberum Capital estimates Ombrina could be worth 18p a share if developed.

Fellow Italian-focused junior Independent Resources (IRG:AIM) was also in demand, gaining 4.7% to 8.38p, after it moved a step closer to getting approval from the authorities for its San Gervasio gas-to-power project - the company says it expects a formal award of the necessary production concession in the near-term.

Kazakhstan-based energy minnow Max Petroleum (MXP:AIM) ticked up 2.4% to 4.25p after it announced its ZMA-A20 development well had encountered hydrocarbons as expected.

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Issue Date: 22 Feb 2013