Unique morphology of Zimbabwe diamond and its “fingerprint” characteristic significance

In recently years, the discovery of a superlarge diamond secondary deposit from the Marange diamond orefield in Zimbabwe has aroused international cooperation between China and Zimbabwe activities in such aspects as geological exploration, mining, and diamond cutting. Therefore, a systematic mineralogical investigation of the diamonds from Zimbabwe was performed to find their characteristic features. It is found that the crystals display characteristic morphology and surface microstructures. The "cross" dissolution pattern consists of a large number of tiny square-shaped etch pits distributed in 100 direction on 100 faces. The red spots on the surface are caused by selective growth of iron oxide minerals along the edges and at the corners of the etch figures. The results could have reference value for studying the geochemical environment of the ore deposit.