. Fig, Pyriteous structures associated with brachiopods (sample EST12436) ? (a) macroscopic perpendicular view of a pyrite layer and a longitudinal cross-section of brachiopod shell; (b) macroscopic top view of broken pyrite layer; (c) microscopic view of longitudinal cross-section of brachiopod showing the pyrite and calcite filling

. Rhynchonella, of the shell; (b1) cross-section parallel to the shell (transmitted natural light); (b2) cross-section perpendicular to the shell (transmitted natural light); (c) detail of a shell section observed in cathodoluminescence providing evidence of relictual bioaragonite

. Terebratula, of the shell; (h) sub-parallel cross-section of the shell providing evidence of numerous tubular structures filled by diagenetic pyrite (black points) (transmitted natural light); (i) detail of the shell showing tubular structures filled by pyrite and wellpreserved organic micro-structures

. Fig, Limestone sample Bure 3 from the gallery -(a) Replacement and infilling of shells by chalcedony; (b) Infilling of shell by cm-sized euhedral crystals of celestite; (c) microscopic view of the shell replacement by calcite and chalcedony (polarized transmitted light); (d) limpid euhedral grains of calcite encapsulating euhedral dolomite and glauconite (natural transmitted light); (e) infilling of shell by celestite and chalcedony (natural transmitted light)