Philippines-focused miner Medusa Mining saw earnings before interest, tax, depreciation and amortisation double to $63.3m in the six months to 31 December 2010 from $31.5m in the second half of 2009. Revenues surged to a record $78.3m from $41.3m the year before, due to increased gold production and a higher price received on sale of gold. Medusa received an average gold price of $1,291 per ounce from the sale of 48,883 ounces of gold for the half-year to December 2010; in the second half of the preceding year it had sold 39,162 ounces at $1,047 per ounce.Engineering specialist Kentz Corporation has won a $35m five-year contract from the National Petroleum Refiners of South Africa (Natref) to perform shutdown management and execution services at the Natref crude refinery in Sasolburg, South Africa.Shares in southern Johannesburg gold miner Central Rand Gold bounced back from their recent lows after the South African government approved the recommendations made by the team of experts to the Inter-Ministerial Committee on acid mine drainage in the Witwatersrand.The company had warned on 3 February that inaction on this issue could jeopardise its future, and put itself into cash conservation mode.Baobab Resources moved up after an update on its iron/vanadium/titanium project in Mozambique."Analytical results have been returned from a three hole RC (reverse circulation) drilling cross section located in Block 1, the southernmost portion of the South Zone prospect," the company said. "A broad, 140m wide, body of heavily mineralised magnetite is being delineated."Veterinary pharmaceuticals company Dechra said it was experiencing 'competitive markets' as it posted a fall in profits in the half year to 31 December.Pre-tax profits fell to £9m from £9.7m as revenues climbed to £192.2m from £184.8m, helped by acquisitions.Shares in Gleeson fell after the housebuilder and land dealer sounded a decidedly gloomy note on the housing market as it posted a loss for the six months to 31 December."The extremely cautious approach of mortgage lenders and the widespread uncertainty regarding employment prospects makes it likely that the housing market overall will remain subdued for some time," chairman Dermot Gleeson said. "However, the action taken over the last year to reduce costs substantially without compromising quality means that the Group is now able to offer buyers at the lower end of the market homes that are very competitively priced."Pre-tax losses totalled £701,000, against a profit of £128,000 over the same period the previous year as revenue fell to £24m from £27m.First half revenues at African agricultural company Agriterra more than doubled to $5.28m, from $2.48m previously, after turnover at its maize business hit a record high. The group also swung to a pre-tax profit of $97,000 in the six months ended 30 November, compared with a loss of $1.97m in 2009.Agriterra started the period with a strong stockpile after a record buying year in 2009, which enabled it to "manage the processing and sales of the product in-line with the recent favourable pricing environment," the group said.A 24.6% increase in the average gold spot price in the first half helped Pan African Resources' revenues grow by 32% to £38.33m, from £29.04m in 2009. The jump in revenues was also aided by the depreciation of the pound against the South African Rand.Earnings before interest, tax, depreciation and amortisation rose by 51% to £12.95m, while earnings per share grew 56% to 0.53p.