(ShareCast News) - Diamond development company Firestone Diamonds has extend to 29 August the date at which all conditions for the $8m disposal of its Botswana operations to Tango Mining Ltd must be completed."This extension is to enable Tango Mining to finalise the proposed $30m loan commitment with Vanderbilt Commercial Lending," said Firestone.That sum would go to financing the deal, and to Tango Mining's recommencement of operations at the BK11 mine.