Below are some of the main news-driven share price changes at 11.00am.
RISERS
Amur Minerals (LON:AMC), up 87.5%. A production licence has been awarded for the base metals specialist's Kun-Manie nickel copper sulphide deposit in Russia.
Tungsten Corporation (LON:TUNG), up 30.0%. Some much-needed cheer for Tungsten shareholders, as the share placing went better than expected. The company raised £127.5mln after placing shares at 80p a throw.
United Carpets (LON:UCG), up 16.7%. The UK's second largest chain of floor covering retail outlets has declared a special dividend of a penny a share. That may not sound that big a deal, but with the shares trading at less than 10p before the announcement – they have risen 1.5p to 10.5p – that is a fairly handy yield.
FALLERS
Plus500 (LON:PLUS), down 23.6%. Trading in the shares was suspended at 10.15am, pending an announcement, but that still left enough time for the company to lose around a quarter of its market value.
Mosman Oil & Gas (LON:MSMN), down 13.5%. The company is doing some flow testing at Petroleum Creek, but, despite the promising name of the creek, recovered fluid thus far has been predominantly water.
W Resources (LON:WRES), down 6.9%. The tungsten, copper and gold production, exploration and development company with assets in Spain and Portugal saw its first revenues in 2014, but it is still an early stage company, and loss before tax widened to £641,000 in 2014 from £253,000 in 2013.