A Photosynthetic Cyanobacterium Candidatus Gloeomargatia lithophora performs biomineralization i.e.formation of minerals (ca,mg.barium,strontium) intracellularly (importantly calcium carbonate) while other organisms are known to form extracellularly.
Inclusions of calcium,magnesium,barium,strontium carbonates
seen inside the cyanobacterium.
http://www.sciencedaily.com/releases/2012/05/120511101352.htm
