Morphology of crystals observed at the surface of the colonies of marine bacterial strains inducing biomineralization. Marine bacteria grew on solid isolation media for 3 days at 28 °C. The average crystal length depends on the strain. CD7: 30 μm; CD2 and CD8: 50 μm; CD3, SW1 and SW3: 60 μm; CD1: 70 μm; CD4, CD9, CD10, SW2: 90 μm; Md1:100 μm; CD5 and CD6: heterogeneous. Sporosarcina pasteurii DSM 33: 30 μm.