Fig. 4From: Hematite (α-Fe2O3) quantification in sedimentary magnetism: limitations of existing proxies and ways forwardFirst derivative of IRM acquisition (gradient) curves and hematite components for 7-T maximum applied fields. Results for hematite pigments in a decorative ‘print stone’ from the Mount McRae Shale Formation, Western Australia (Abrajevitch et al. 2014): a hematite print stone pigment (sample pps11) and b uniform pigment (sample TOM07). Results from Abrajevitch et al. (2015) for: c Paleogene limestone 21 cm above the K–Pg boundary at Bottaccione Gorge, Italy, and d limestone 46.5 cm below the boundary. Abrajevitch et al. (2015) identified five components; for clarity, only the hematite (labelled H) component of interest here is shown. Dashed vertical lines represent the 300-mT cut-off fieldBack to article page