Polished fossil stromatolite. Domal from Irregully formation IRR131

IRR 131    Fossil stromatolite slab, polished on one side.

Totally replaced by colourful chert !

From the Proterozoic "Irregully Formation", age approx. 1.1 billion years.   

Dimensions at widest points approximately 150 mm x 110 mm x 11 mm thick.

It weighs 340 grams..