Multivariate Analysis of Writing Inks: A Forensic Application of EDXRF and ANOVA

Ink analysis is crucial while performing a forensic investigation as it helps identify significant financial and legal documents. By dating and describing the writing ink used on a document, its validity can be established. The study's objective is to determine the chemical composition of 126 writing inks of different types and colors using Energy Dispersive X‐ray Fluorescence Spectrometer. For the intergroup and multiple correlation of the major and trace elements found in the writing ink samples, the statistical methods of one‐way ANOVA and the post hoc test were applied. The values of different elements in the five groups of ball and gel inks were compared using one‐way ANOVA, and the findings showed that the values of the elements CuO and SiO were statistically significant ( p < 0.01) and varied among the different groups of inks. The Tukey HSD post‐hoc test was performed to compare the five groups pairwise. In the comparison, it was found that the MnO and CuO elements differed significantly in each of the five groups. The study's findings demonstrate that Energy‐Dispersive X‐ray Fluorescence Spectrometer is a suitable method for determining the chemical makeup of writing inks. The results of the study support the idea that the chemical components found in the various writing ink types can be effectively used to characterize the inks using spectroscopic techniques and chemometric methods.