Figure 2 in A king-sized theropod coprolite

Figure 2 Photomicrograph of a thin section of the theropod coprolite, showing sand- to pebble-sized bone clasts within a microcrystalline phosphatic ground mass.The elemental composition of the ground mass is similar to that of the bone fragments, indicating that it is probably largely composed of reprecipitated bone apatite infiltrated by clay minerals from the host sediment (Table 1). The large bone fragment in the upper left portion of the image exhibits a fibrolamellar pattern, with osteocyte lacunae concentrically arranged around the vascular canals. Probe measurements of the interior of bone lacunae revealed that many of these channels are at least partially empty, whereas others exhibit variable element distributions, with generally lower concentrations of calcium and phosphorus, and higher silicon and aluminium levels (Table 2). Scale bar, 400 m.