Long Cecil is a cannon built in the workshops of the De Beers mining company in Kimberley for use by the British in the Siege of Kimberley during the Second Boer War.

The De Beers Group is a South African- British corporation that specializes in diamond mining, diamond exploitation, diamond retail, diamond inscription and grading services, diamond trading and industrial diamond manufacturing sectors. The company is active in open-pit, underground, large-scale alluvial and coastal mining. It operates in 35 countries with mining taking place in Botswana, Namibia, South Africa, and Canada. It also has an artisanal mining business, Gemfair, which operates in Sierra Leone.