The role of fungi in the diagenetic alteration of spar calcite

Fungi may play a far more important role in carbonate diagenesis than has been previously suspected. This can be demonstrated by placing known species of fungi on crystals of Iceland spar calcite. Such experiments show that fungi can (1) cause sparmicritization through dissolution, (2) produce spiky calcite through dissolution, (3) trap and bind loose particles of calcite, and (4) promote the growth of new calcite crystals. Although not observed in this series of experiments, fungi can bore into substrates and cause sparmicritization. The activity of fungi involves a complex interplay of substrate destruction and construction without the intervention of vast quantities of fluid.