UK Stocks-Factors to watch on April 24

April 24 (Reuters) - Britain's FTSE 100 index is seen opening 10 points higher at 7,409 on Tuesday, according to financial bookmakers. * GLENCORE: Shares in Glencore-owned Katanga Mining Ltd lost half of their value on Monday and cobalt markets were on alert after the company said the Democratic Republic of Congo's (DRC) state-owned mining company had taken steps to dissolve its local copper and cobalt unit. * ROLLS-ROYCE: Rolls-Royce may transfer the design approval process fo