in the eroded core of the Blackdown pericline, Shipham
and the neighbouring hamlet of Rowberrow were once the centre
of the zinc mining industry on Mendip. Both villages are underlain
by the Triassic Dolomitic Conglomerate, which overlies the Devonian
sandstones of the Portishead Formation.
Aerial view of Shipham and Rowberrow (click to enlarge view).
The discovery of zinc
ore in the 16th century turned the small settlement at Shipham,
noted in the Domesday Book, into a major
mining centre. Calamine and smithsonite, along with some galena occur
in veins in the Triassic Dolomitic Conglomerate. The veins mostly
lay close to the surface and were worked in numerous small mines
and pits, some of which are still accessible to cavers. They were
generally only 30–40 m deep and were usually worked by hand
with only the aid of a hand-turned windlass and a bucket. Areas of
gruffy ground, a local name for the hummocky ground formed by the
remains of old mine workings and waste can still be seen south of
Many people living in Shipham were reliant on mining for income and
life could be tough and squalid. The miners of Shipham were notorious
for being rough, and it was reported that no constable would arrest
them for fear of disappearing down one of the many mine shafts.
Cross-section from Shipham Gorge to Churchill Gate showing mineral
veins (click to enlarge view).
Hannah More, the well-known philanthropic writer, was appalled by
the poverty in the area, and in 1790, with the help of William Wilberforce,
the well-known social reformer, was instrumental in setting up
both a Sunday school and a day school, as well as the first of
the 'female clubs' on Mendip.
The legacy of mining also remains in the form of heavy metal contamination
of the soil. Shipham has the highest levels of cadmium in the soil
anywhere in the UK. Cadmium is a toxic metal associated with old
zinc mine workings. However, a study found that the cadmium in the
soil is tightly bound up in minerals, and is not readily available
for uptake by plants. It therefore does not enter the food chain
and has no measurable effect on health.