My family went walking over Coldham’s Common in the east of Cambridge on Sunday, and climbed what my children know as the mountain. The mountain is a tiny hill a few metres high, tiny but very steep-sided. In Cambridgeshire it is the nearest thing we have to a mountain.
I have no idea why it is there, but I do know that Coldham’s Common was, at the end of the nineteenth century, a site of extensive coprolite mining.
Coprolite is fossilised dinosaur dung, high in phosphates and valuable as a fertiliser. It was first identified by the geologist William Buckland, who built on Mary Anning’s observation that clusters of the mineral she knew as bezoar stones were often found in the stomach region of fossilised ichthyosaurs, and that if these bezoar stones were broken open they frequently contained fossilised fish remnants and occasionally the fossilised bones of smaller ichthyosaurs. In 1829 Buckland proposed that the stones were in fact fossilised faeces, and named them accordingly.
The coprolite mined in Cambridgeshire, chiefly around Cambridge and Ely, was refined in Ipswich, where there is still a Coprolite Street. By the end of the century the coprolite mining industry was in sharp decline, but revived briefly during the First World War when the phosphates were used in munitions.
So I don’t know for a fact that the mountain on Coldham’s Common is in fact a slagheap of dung, but it pleases me to think so.