Botswana and diamond miner De Beers announced on Saturday they had reached an 'agreement in principle' on a new 10-year sales agreement. This came hours after the previous sales agreement expired on Friday, 30 June, so there must have been some serious nail-biting in the boardroom.

A diamond may be forever, but an agreement to sell or mine the precious gemstones is not.

De Beers and the government of Botswana, after lengthy and at times apparently tense negotiations, finally clinched a 10-year new sales deal to 2033 as the old one expired. De Beers produces rough diamonds in Botswana, the world's second-leading source of the gemstones after Russia, through Debswana, a 50-50 joint venture with the government. Anglo American has an 85% stake in De Beers.

In the terse statement that was issued on Saturday, no details of the agreement were unveiled.

"The transformational new agreement between Botswana and De Beers reflects the aspirations of the people of Botswana, propels both Botswana and De Beers forward, and underpins the future of their Debswana joint venture through long-term investment," it said.

"While the partners finalise the implementation of the formal Sales and Mining Agreements, an Interim Agreement will preserve the terms of the most recent Sales Agreement, which expired on 30 June."

This signals that some i's are still being dotted and some t's are still being crossed, which means that some lawyers are coining it. Agreement in principle was also reached on new 25-year Debswana mining...