Assessment of three major decomposition techniques for sample preparation during elemental analysis of granite rocks

Abstract

Three main rock-decomposition techniques; microwave oven, open beaker acid and basic fusion were examined in an attempt to establish the most appropriate method for the decomposition of granite rocks for elemental analysis. Standard reference rock material NIM- SARM-I was dissolved using each of the digestion techniques and the solutions analyzed using an Inductively Coupled Plasma-Mass Spectrometery (ICP-MS) analytical system. Element concentration data for Al, Cr, Mn, Fe, Na, Mg, K, Ca, Ti,Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Ba, La, Ce, Pr, Nd, Sm, Ru, Gd, Th, Dy, Ho, Lu, Pb, Cd, Th, and U were obtained. This work shows that no single decomposition technique can adequately attack all the mineral structures containing the elements as is evidence in the agreement or disagreement of the results when compared with the SARM-I certified values.

Nigerian Journal of Physics Vol. 16(2) 2004: 15-20