CLEO: Common lead evaluation using Octave

Common lead isotopic data can provide important information on the history and the evolution of geological samples. Evaluation of common lead datasets need specific calculations e.g. iterative Pb207/Pb206 age calculation, linear regression with correlated errors and sometimes principal component analysis (PCA). These calculations can be performed by modern computers, but a set of pre-defined functions would be helpful, as these calculations are not always trivial.This paper presents an implementation of some basic functions for Octave, a GNU public license program, for the evaluation of common lead data. To show the capability of the script, a common lead dataset for the Dlhá Dolina intrusion is presented and evaluated using CLEO. The timing of this evolved magmatic body can be constrained by the WR–Pb–Pb method to a minimum age of 231±6.5Ma.