Copper is generally considered to be adsorbed more easily than other metal ions (Coşkun et al. 2006), however, this has been shown to not always be the case as the capture of Copper by some sorbents is highly dependent on pH (Wu and Zhou 2009). Unfortunately, in this current study no measurements of pH were recorded despite the potential for changes in pH to be caused by chemical reactions between the dissolved metal compounds and the shell material (Genç-Fuhrman et al. 2007, Wu and Zhou 2009).