Figure 20. Primary and secondary porosity in rudist grainstone, Upper Cretaceous, road to Porto Vromi (2 km from port), Zakynthos.
Rounded but very poorly sorted rudist biosparite to packed rudist biomicrite. Abundant, well rounded rudist fragments plus subordinate corals and benthic forams. Very poorly sorted, and in patches of zones surrounded by biofragmental matrix.  Numerous micrite envelopes and spectacular leaching to produce 30+ percent moldic porosity.  Thin, blocky, nonferroan calcite cements both inside and outside molds. Long dimension = 5.75 mm.