Cations and Anions found in the Soudan Mine. The pie chart shows the abundance of cations and anions found in the mine. The numbers in parentheses are the concentrations (in ppm) of each ion in the "Black" and "Red" samples respectively. The minor ions are shown expanded in the rightmost pie.
Edwards et al. BMC Genomics 2006 7:57 doi:10.1186/1471-2164-7-57