Accurate and precise lithium isotopic determinations of igneous rock samples using multi-collector inductively coupled plasma mass spectrometry Original Research Article

A second-generation multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) was applied to lithium isotopic measurements. The high sensitivity of the ICP-MS enabled high precision (±0.82‰, 2σ) analyses with small amount of Li (∼45 ng Li). A single-step column separation protocol was established with which rapid purification of lithium from rock solutions can be carried out with reduced blank (<10 pg). The influence of potential sources of error for acquisition of lithium isotopic data introduced during the separation, such as matrix effects and isotopic fractionation due to incomplete recovery, were examined with an artificially mixed solution of a composition similar to that of basalt, which was doped with Li isotopic standard reagent. The examinations demonstrated that our protocol suffered from negligible isotopic fractionation.