Artisanal And Small-Scale Mining In Africa: Opportunities And Challenges

It is important to recognise that the concept of ASM encompasses a wide range of mining practices. In certain areas artisanal mining has been a traditional activity for generations, and may be a seasonal enterprise to supplement agriculture-based livelihoods. In some cases significant commodity price fluctuations, mining closures or other economic shocks may lead to large numbers of ASM miners moving rapidly into an area, often with associated stresses to the environment and local communities. ASM mining may occur with various degrees of sophistication, mechanisation and legality. Some of the negative aspects of ASM mining include poor health and safety practices, child labour, pollution (for example, mercury contamination of water systems by ASM gold miners) and mining in conservation areas.
http://www.polity.org.za/article/artisanal-and-small-scale-mining-in-africa-opportunities-and-challenges-2012-03-05