With respect to Pb, the significant underestimation of its content with the aqua regia extraction in two of the samples can be expected since Pb is mainly held at aluminosilicate sites that are moderately resistant to acid dissolution
With respect to Pb, the significant underestimation of its contentwith the aqua regia extraction in two of the samples canbe expected since Pb is mainly held at aluminosilicatesites that are moderately resistant to acid dissolution