One of the shopping malls, The Grand Arcade, in the centre of Cambridge, England, is paved in a beautifully rich creamy coloured stone, polished to perfection. And embedded in the stone and visible on the polished surface are fossils of animals and plants that lived millions of years ago. It’s probable that few of those walking through the Arcade notice these reminders of the past: they are intent, of course, on their shopping, looking at the shops, looking to see where they can get a cup of coffee. The management of the Arcade keep it beautifully clean: the stones aren’t disfigured by the detritus of chewing gum that blight so many pavements these days, so that the fossils can’t be mistaken for dirt.
It’s not easy to identify the fossils: all you can see is a one-dimensional slice through the fossil. But you can tell that some of of them are fishes, and there are a substantial number of ammonites, see in cross-section. Ammonites were free-swimming cephalopods, relatives of modern-day squids, that survived in the oceans for over 200 million years, only to be blasted into extinction after a massive body from outer space, about 10km in diameter, crashed into earth near what is now known as the Yucatan peninsula in Mexico. This was a turning point in earth’s history, and we are reminded of these creatures as we walk through the Grand Arcade.
This isn’t the only place you can see stone with embedded fossils from earth’s remote past. Many of the corporate headquarters of global businesses in the city of London are enhanced by facades of such polished stone, and some of them also contain such fossils, often much larger and more beautiful than those in the Grand Arcade. And only a few minutes walk from the Grand Arcade, in the Museums of Zoology and the Sedgwick Museum of Earth Sciences, you can see even more magnificent fossils, named and labelled, appropriately for these scientific departments of a university.
Another interesting place to see fossils embedded in a building is The University Centre in Cambridge, faced with Portland Roach stone, which is particularly rich in fossils. Portland stone was used throughout England for facing building, since it is particularly hard-wearing. In fact, as you look around you will find these reminders of the past everywhere.