(Sharecast News) - AIM-listed explorer Botswana Diamonds revealed that Vast Resources, with which it has signed a memorandum of understanding to develop diamond resources in Zimbabwe, has been awarded exclusive access to a diamond concession in the African nation's Chiadzwa region.The concession, now known as the Marange Diamond Fields, was covered in Botswana Diamonds' agreement with Vast, with the pair seeking to realise the full potential of the area.Botswana Diamonds said the purpose of Vast's agreement with a community organisation was to carry out initial due diligence on the area with a view to concluding a joint-venture agreement, the principal terms of which have been agreed, for exploration, mining and marketing.The 15 square kilometre Heritage Concession is located close to an area of Vast's historic Marange Diamond Fields claim and is believed to be an extension of the same geological system.John Teeling, chairman, said, "I am delighted that Vast has been awarded this exclusive access to part of the famous Marange diamond fields and we look forward working with them to realise the full potential of this area and others as they begin to emerge with Zimbabwe opening for business."As of 1200 BST, Botswana Diamonds shares had climbed 7.37% to 1.02p, while Vast Resources shares had expanded 5.12% to 0.65p.