Sample of calcareous pisolithic

11 cm high. The São José de Itaboraí Basin, located in the municipality of Itaboraí, Rio de Janeiro, is one of the smallest Brazilian sedimentary basins and one of the most important fossiliferous deposit of paleoceanic age in Brazil and in the world. It was discovered in 1928 and had the calcareous explored until exhaustion by the cement industry. Pisolithic limestone, the most notable lithology of the basin, is no longer found in outcrops.