Specimen Calc10. (a to c) Images of the top of the specimen as received, after freeze drying, embedding and first polishing, respectively. (d to f) Fourier Transform Infrared microspectroscopy in reflectance mode (FTIR-RM) protein and mineral maps and visual map, respectively, of the first exposed plane. (g to i) FTIR-RM protein and mineral maps and visual map, respectively, of the second plane. (j and k) Images of the bottom of the specimen as received and after freeze drying, respectively. (l to n) Visual map and FTIR-RM protein and mineral maps, respectively, of the bottom after embedding and polishing. The distance between the second polished plane (i) and the shaved bottom (l) is 1.8 mm. All FTIR-RM maps were obtained with 180 × 180 μm spatial resolution (SR). Blue is the largest area under the related peaks and red is the lowest in the FTIR-RM maps. The individual size scale bars appear on the images and the maps.