There exist many definitions of stromatolites. Most authors regard them as laminated calcareous structures. In a comparative study of oöides by Kalkowsky (1908) in Germany he mentioned the term stromatolites for the first time. The definition of Walter (1976) "organo-sedimentary structures" is also often used. However, he does not mention the biomineralized carbonate after finding non-calcareous stromatolites in Precambrium rocks. Walter retains the "fine laminated biogenic sedimentary structures" produced by sediment trapping and binding as a result of the activity of agglutinating micro organisms. In a third edition (Krumbein, 1983) the sedimentary particles are excluded. According to Riding (1993) the lamination is a result of the biomineralization and/or precipitation (carbonate, gypsum, silica group) and named them "tufa stromatolites". The "iron containing rhytmic fungal silcrete" in the article of Jannink (1994) is non-typical. In general the name "biogenic mats" can be used.