ARMADILLO_VolcaNorm: An open-source, macro-enabled VBA for Excel™ spreadsheet for calculation of CIPW norms and IUGS igneous rock classification for volcanic rocks

ARMADILLO_VolcaNorm is a versatile, user-friendly, open-source, macro-enabled spreadsheet that can rapidly calculate CIPW normative mineralogy ( viz ., “a norm”) and classify volcanic rocks following IUGS recommendations entirely within the Microsoft Excel™ environment. The program can process up to 10,000 major-element analyses of volcanic rocks, with the user specifying whether total iron is reported as FeO* or Fe 2 O 3 * and selecting one of seven methods of re-partitioning iron (or providing a custom value), including options that incorporate temperature, pressure, redox buffer, and offset. ARMADILLO_VolcaNorm outputs the FeO/FeO* ratio for each sample, computes the normative mineralogy, and applies total alkali-silica (TAS) and norm-based criteria for accurate classification. It can also generate customizable TAS diagrams with labeled samples. Unlike previous tools, ARMADILLO_VolcaNorm operates seamlessly within Excel, enabling simple copy-and-paste workflows and enhancing reproducibility and accessibility in igneous petrology. • ARMADILLO_VolcaNorm: an open-source VBA-based Excel™ spreadsheet to classify volcanic rocks. • A macro-enabled spreadsheet capable of rapidly calculating CIPW normative mineralogy • A program set for handle large dataset of bulk and glass compositions of volcanic rocks.