Rough Natural Ordovician Stromatolite

This sromatolite is in its natural form, though it has been cut to have a flat surface on the back. The back has not been polished. This very displayable collector piece exhibits the classic rings characteristic of stromatolite growth.

Of scientific interest is the age, Lower Ordovician, some two Billion years after stromatolite reached its peak on Earth, and during a time when stromatolite niches were disappearing because of competing metazoan and benthic life forms. The final major decline of stromatolite on Earth was a mere 50 million years after this stromatolite was formed.