Jan 29, 2009· They also estimate that > 3,000 children are directly employed in artisanal mining in Tanzania. Children engaged in artisanal mining cut across a wide range of ages. In a 1998 survey summarized by Gueye (2001), about 59% of 500 children working at artisanal mining sites in Burkina Faso were ≤ 12 years of age.