27 Aug 2013

When excavation work begins for a building project, you can never be too sure what lies beneath the surface. A seemingly uninteresting large round rock resembling nothing more than a lump of concrete was unearthed At Bishop’s Stortford College Prep School. On closer inspection, it was identified as one of the world’s rarest rocks, Hertfordshire Puddingstone, a conglomerate of small flint pebbles naturally cemented together by silica from sand and silt to form exceptionally hard solid rock.

Formed millions of years ago by the precise conditions prevailing locally during the last Ice Age, almost all puddingstone in the world is found in Hertfordshire. The name arose from its plum-pudding appearance when sliced through.

The story of Hertfordshire’s distinctive stone began in the age of the dinosaurs, but exactly when and how it formed continues to have an air of mystery about it. Its enigmatic nature gave rise to superstitions that it possesses strange powers, such as growing in fields, repelling evil, and breeding.

Rock similar to the sand matrix of Hertfordshire Puddingstone, and with similar silica cement, but lacking the pebbles, occurs further west in Southern England, and is called Sarsen stone. Stone Age man used large blocks of it for the Trilithons of Stonehenge and the stone circles and avenue at Avebury (Wiltshire).

“It’s a fascinating discovery,” said Estates Manager John McDonagh. “Linda Hamling, the secretary of the Hertfordshire Geological Society, was one of my first contacts when it was uncovered and she kindly gave me a lot of background information.

Now expertly cut and polished, the county’s latest puddingstone discovery, which weighs around two and a half tonnes, will be displayed at the entrance of the most recent building project at the independent school based in East Hertfordshire, close to the Essex border. Further information about the puddingstone phenomenon can be found on the East Herts Geology Club’s website:

The major development at Bishop’s Stortford College Prep School involves the rebuild of around a third of its accommodation in order to enhance the facilities for its 450 girls and boys aged 7 to 13 years. The Prep School is part of Bishop’s Stortford College, a co-educational, day and boarding school located on a beautifully spacious 130-acre campus, with a total of 1130 pupils aged 4 to 18 years.

A new building will house a new library, a drama studio and nine classrooms, whilst the main Prep School building is being extended to provide a fourth science laboratory, as well as a new reception area and administration offices.

Incorporated into the project are more than 25 square metres of solar panels, a mixture of solar PV and solar thermal, to supply a substantial proportion of the Prep School’s electricity.

After the extended and enhanced accommodation opens in the Autumn, existing classrooms in what is known as the Meadows Building will be removed to create additional play space for the pupils and relocate the school’s second art room into a larger home, where the current library is located.

Commenting on the project, College Headmaster Jeremy Gladwin said: ‘The new project is the most extensive so far undertaken at the College and will enhance significantly the facilities for our Prep School pupils. With this work nearing completion, we are already in the early stages of planning our next major project, which will focus on further developing facilities in the Senior School. The next five years will see the most ambitious building developments for over 100 years and will be a fitting way to mark the College’s 150th anniversary in 2018.’