UK coal producer ATH Resources fell into the red at the half-year stage as bad weather last autumn and winter hit production, leaving turnover down 4% at £34.4m.The company lost £2.9m in the six months ended 4 April compared with a profit of £0.1m in 2009, and now expects full-year production volumes to be 60,000 tonnes lower than forecast at around 1.75m tonnes. "As the group works through its newly improved contract base it will be able to access a rapidly improving coal market leading to significant improvements in future profitability," said boss Tom Allchurch.Firestone Diamonds is up today following news that Debswana has decided to proceed with the modular tailings treatment project at the Jwaneng mine in Botswana, and as production at Firestone's BK11 kimberlite nears. The Jwaneng tailings project, to be built by Firestone, could contribute up to $150m in toll treatment revenue for the company.In a separate statement, the AIM-listed firm said the start of production at BK11 will make it one of only three kimberlite producers worldwide outside of the major mining companies. London Mining says a new prefeasibility study for its 100% owned Isua magnetite project in Greenland considers a 21-year 10 million tonne per annum high-grade concentrate operation.The new study incorporates budgetary quotes from Sinosteel and China Communications Construction to deliver a total project capital cost of US$1.74bn with an average operating unit cost per tonne of concentrate of US$27.13.