Six suspects were arrested in possession of an unpolished diamond, at Kleinsee, on Thursday.
They were arrested by a joint crime-combatting operation by South African Police Service members from Port Nolloth and Kleinsee and a private security company.
The two men, aged 30 and 32, were arrested at a residence in Derde Street.
Police also seized five bags of suspected diamond-bearing gravel.
Investigations are underway to determine the origin of the diamond, its composition and whether it is linked to illegal mining.
Picture: Suburban Control