Fig. 4 in Aragonitic rostra of the Turonian belemnitid Goniocamax: Arguments from diagenesis

Fig. 4. Minor element contents (in ppm) in Recent shells. A. Average compositions of inner prismatic and outer prismatic aragonite layers in Sepia and Spirula. B. Average compositions of inner prismatic, nacreous and outer prismatic aragonite layers in Nautilus macromphalus. C. Average compositions of crossed lamellar aragonite layer in gastropods; in the nacreous aragonite layer in Pinna nobilis, and foliated calcite layer in Pecten.