Ichthyoliths—microfossil fish teeth and shark dermal scales (denticles)—are found in nearly all marine sediments. Their small size and relative rarity compared to other microfossil groups means that they have been largely ignored by the paleontology and paleoceanography communities, except as carriers of certain isotopic systems. Yet, when properly concentrated, ichthyoliths are sufficiently ab...

Calcareous microplankton shells form the dominant components of ancient and modern pelagic sea-floor carbonates and are widely used in palaeoenvironmental reconstructions. The efficacy of these applications, however, is dependent upon minimal geochemical alteration during diagenesis, but these modifying processes are poorly understood. Here we report on new biomineralization architectures of pr...

Some time ago Buick (1984) cast doubt on both the biogenicity and the age of the objects we described as Early Archean bacterial microfossils in a previous paper (Awramik et al., 1983). He presented new evidence significant to the interpretation of these objects, but his report also contains statements that may be misleading. We wish to comment on his new evidence and to correct the misleading ...