A practical guide to the double-spike technique for calcium isotope measurements by thermal ionization mass spectrometry (TIMS)

The double spike technique is the most reliable method for calibrating instrumental and chemical mass-dependent fractionation, which has been widely applied in isotopic analysis of many elements such as Mo, Sn, Ru, Ca, etc. However, practical use of double spiking is possibly hindered by the perceived difficulties in proper double spike calibration, mathematical inversion and data reduction. In this study, we will refer to Ca double spike on how to yield excellent isotopic data on TIMS. A detailed description on how to choose and calibrate an optimal double spike is presented. Our main aim is to provide a practical guide when working with double spike, especially for researchers in new isotopic systems. (C) 2020 Elsevier B.V. All rights reserved.