- After discovering BK18 in 1990, De Beers through its delineation drilling estimated the size of BK18 as being only a 1 hectare kimberlite which is a complete mismatch with the large size of its associated magnetic anomaly in both airborne and ground magnetic surveys conducted.
- Insufficient mineral chemistry analysis was performed on BK18 to assess its potential.
- The large size (>5ha) of the magnetic dipole was confirmed by subsequent explorers AfriOre and Firestone, and while AfriOre did not conduct any drilling, a combination of De Beers and Firestone delineation drilling did not constrain the SW portion of the kimberlite, thus there exists potential for a larger body than current interpretations.
- Macro-diamonds totalling 0.3carats were recovered by De Beers from analysis of just over 1 ton of kimberlite material, confirming the diamondiferous nature of the kimberlite in a sample size that is considered considerably inadequate to give any reliable indication of economic potential.
- Micro-diamond analysis on cored kimberlite was never carried out. Results of micro-diamond analysis on sub-optimal drill-chip material purportedly carried out by Firestone was never reported and there exists considerable doubt as to whether any material was even submitted for analysis.
- BK18 is one of the last of the Orapa area positively diamondiferous kimberlites not to have been adequately assessed for either micro- or macro-diamond content. Given the generosity of the Orapa area cluster in terms of high proportion of economically profitable mines, and the possibility that it is larger than previously thought, BK18 represents a very promising under-explored opportunity.
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