Novel modified electrochemical method were used to analyze sedimentary, metamorphic, igneous, fined grained, coarse grain granite, granite with feldlaths and ferrogenous sand stone rocks along with boulangerite, stibnite, magnetite and scheelite ores for the presence of silver. Rocks and ores samples were processed through fire assay and acid digestion methods. Effect of various interfering metal ions was studied and it was observed that Hg(I) ions contributed maximum increment in the peak current of Ag(I). Differential pulse anodic stripping voltammetry (DPASV) and cyclic voltammetry (CV) were applied for the determination of silver. Glassy carbon bare and modified electrodes were used as working electrodes. Platinum and saturated calomel electrodes were applied as auxiliary and reference electrodes respectively. The modified method has high affinity, selectivity and sensitivity and can be applied for trace level determination of metal ions. The limits of detection (LDL), quantification (LOQ) and linear regression coefficient (R2) were found 1.14µg/L, 3.2µg/L and 0.9969 respectively.


Afzal Shah, Salah Ud-Din Khan and Usman Ali Rana