Four small diamond pipes (B/K1, B/K9, B/K12 and B/K15) were discovered between 1967 and 1972 in an area 20km east of the Orapa kimberlite pipe. These pipes were grouped to form the Damtshaa Mine, the youngest of the Debswana mines which began operation in 2003, and are managed along with Letlhakane Mine from the Orapa operation. The ore grade for B/K9 and B/K12, the kimberlites currently mined, is about 29 cpht and annual production is a maximum of about 330,000 carats. B/K9, at 11.5 hectares, is the larger of the two mined pipes and has a current area of excavation of about 21 hectares, and a depth below surface of 50m. B/K12 pipe area at surface measures 3.2 hectares and the current area of excavation is 7 hectares, with the pit bottom 63m below ground level. The kimberlites at Orapa, Letlhakane and Damtshaa are all monogenetic (multi-vent) volcanoes.

First discovered in 1966, the Orapa Regime (cluster) consists of Orapa, Letlhakane and Damtshaa Mines, which are open-pit operations using traditional truck and shovel methods, and clustered in a radius of under 25km in the Central District of Botswana.

Damtshaa was placed onto extended care and maintenance in 2021.

Primary crushing The run-of-mine ore (straight from the pit, ungraded or unprocessed in any way), is hauled to the primary crushers. Orapa has two units, Crusher 2 and Crusher, both with ability to feed either plant. The primary crushers reduce the run-of-mine to less than 150mm. Scrubbing and secondary crushing The main function of this stage is to prepare correctly sized feed to the Dense Medium Separation (DMS), and feed envelope for the Orapa plants is 1.65mm to 25mm. Material is reduced to less than the top cut-off size (25mm), and all greater than 25mm material is kept in a recycle loop until repetitive trials eventually reduce the size to less than 25mm. The grits and slimes, material less than the bottom cut-off size (-1.7mm), are screen out for the subsequent thickening. Recrush or tertiary crushing Unlike Orapa 1, the Orapa 2 DMS is configured in such a way that it is split into Coarse DMS and Fine DMS. The Fine DMS floats exit the plant as tailings, and the Coarse DMS tailings are transferred to the recrush circuit. The recrush circuit handles the recycling material from the Coarse DMS that is greater than 8mm but less than 25mm, with the intention of crushing further to a product of less than 8mm. The recrush circuit utilizes high pressure roll crushers (HPRC).

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