My fossil fieldtrip

After a recent trip to Cambridge for an examiners meeting, we found ourselves in Peterborough in the Queensgate shopping centre. Rosie and I used to shop here regularly when we lived in the Fens, but this was my first return visit in years.
The flooring throughout is flagged with polished fossiliferous limestone. To a keen geologist, this is a serious distraction from shopping. Ammonite and goniatite fossils are there in profusion, sectioned by the masonry saw so that their internal structure can be seen
Belenmites are particularly fine, many showing the phragmacone and body chamber quite clearly.
The most obscure fossils are the sponges, often appearing as rings or ovals on the surface of the slabs where they have been sliced through at angles.
Just occasionally, if you look hard enough, there are the odd sponges with a section that shows the base, the crown and the cavity in the middle.

Peterborough is one of my favorite cities. It has a fine cathedral, a good museum, one of the best shopping centres in the country and real coffee shops.