(Sharecast News) - Shares in Botswana Diamonds shone on Thursday after the Aim-listed explorer finalised a development deal with fellow miner Vast Resources.Botswana said it had concluded an agreement to develop Vast's concessions in the "prolific" Marange Diamond Fields (MDF) in eastern Zimbabwe. Vast has exclusive access to the heritage concession in the MDF through an agreement with a local community organisation.Botswana also announced a second deal with Vast, covering the joint development of diamond properties away from the fields through a 50:50 joint venture, but stressed that the main focus remained on the MDF.Chairman John Teeling said: "We look forward to working to realise the full potential of this prospective area and others, as they emerge, with Zimbabwe opening up further for business. Work on the initial due diligence is far advanced." He added that there would be further updates on the project "in due course".Shares in Botswana, which had risen as much as 12% in early trading, were ahead 5% at 98p at midday. Vast's stock was flat at 59p.