What are the potential dangers from diamond mining that affect the ecosystem?
Diamond mining occurs in two forms. Firstly, there are diamonds that are mined from their PRIMARY IGNEOUS source rocks such as kimberlites & lamprophyres. Here, the mining follows, as much as possible, the vertical pipe-like body of the kimberlite. The impact here is not particularly significant since these pits take up relatively little surface area. AN increasing number of diamonds, however, are being mined from SECONDARY ALLUVIAL sources. These occur within horizontal gravel beds, often immediately above a granitic or schistose bedrock. The area is stripped of its vegetation, its soils and the top-most sands. Then, the lower gravel units are mined out with mechanical diggers and fed into a Dense Media Separation plant, sometimes hundreds of tonnes of gravel are excavated to recover a few carats of diamonds. The tendancy is that having been mined, the materials (the processed gravels, the top-most sands and the soils) are not put back in the mined out areas in the manner in which the
