Organisms that selectively mineralize barite (BaSO4) have also been described in the literature.  Barite is a denser mineral (BaSO4 = 4.5 g/cm3) than either celestite (SrSO4 = 3.96 g/cm3) or calcite (CaCO3 = ~2.8 g/cm3). This high mass density favors the fuse of barite in building gravity-sensing statoliths found in some freshwater green algae (Charophytes) and in planktonic flagellates within the class Prymnesiophyceae (Minna R. Krejci et al., 2011). Whether barite is also used in Bacteria or Archaea is unexplored, although the soil microbe Myxococcus xanthus can precipitate BaSO4 under appropriate conditions (González-Muñoz et al., 2003). More generally, it has been noted that BaSO4 precipitates are found in marine systems, despite the very low concentrations of Ba, and this suggests an active and selective biological concentration mechanism (Martinez-Ruiz et al., 2019). 

​