Elemental analysis of phosphate rocks: For sustainable agriculture in Pakistan

The concentration of 32 elements was determined in phosphate rock samples from the Hazara phosphate deposits of Pakistan using instrumental neutron activation analysis (INAA) technique employing different irradiation protocols. These included 23 major, minor and trace elements (Al, As, Ba, Br, Co, Cr, Cs, Fe, Ga, Hf, K, Mn, Na, Rb, Sb, Sc, Sn, Ta, Th, U, V, Zn and Zr) and 9 rare earth elements (REEs) namely Ce, Eu, Ho, La, Lu, Nd, Sm, Tb and Yb. The results have been compared with the global values of these elements. The concentrations for most of the elements studied are lower than the concentrations reported in the literature whereas the concentrations of As, Co, Fe, K, Mn, Na and Sb are comparable. Two samples namely HR-4 and HR-5 have the highest concentrations for majority of the REFs with high enrichment factors. The quality assurance of data was performed through the concurrent use of Lake Sediment (SL-1) and GSJ-JR-1 (Rhyolite) reference materials. The acquired data will serve as a reference for the follow-up studies to assess the agronomic effectiveness of the Hazara phosphate rocks.