Source determination of homemade ammonium nitrate using ATR-FTIR spectroscopy, trace elemental analysis and chemometrics

•Ammonium nitrate (AN) prepared from commercially available products and mixtures.•Multi-modal chemical analysis with chemometrics investigated for source discrimination.•ATR-FTIR spectroscopy was able to distinguish between pure and homemade forms of AN.•Discrimination of all AN samples was achieved via elemental analysis by ICP-MS.•Potential to distinguish grades, precursors, and brands of AN for intelligence purposes.