Fig. 2
From: Planktic foraminifera form their shells via metastable carbonate phases
Microstructure of O. universa shells. a High angle annular dark field (HAADF) image shows the fibrous texture of the chamber and the base of a spine (white rectangle and enlarged in the inset). Note the organic membrane that covers the spine foundation in the inset. The circular features in the sample image are caused by the underlying carbon sample holder. b Bright-field image of the particulate fibres that comprise the chamber wall. c area in foil #4233 showing pores (arrow). Scale bars are 1 µm (a), 50 nm (b) 50 nm (c). Analyses were carried out during session 1
