Britain’s building stones support the foundations of our civilisation. Recent extreme weather events underline this, highlighting the importance of Portland stone for Devon railways. In February 2014, repairs on a section of railway track at Dawlish were called off for safety reasons after the supporting track ballast was washed away. Track ballast, made from crushed Portland stone, supports the railway sleepers and, under usual conditions, maintains drainage of the track. Alarming pictures were published of the bare railway track minus its ballast.
Portland stone is a unique limestone found only on the Jurassic coast of East Devon and Dorset. It was formed over 140 million years ago in the warm, subtropical seas which then surrounded Britain. Calcium carbonate in the sea snowballed around small fragments of coral and shell in the mud of the sea floor, forming spheres called ooliths. Over time, quantities of ooliths compacted together, eventually becoming Portland stone. Its geological origins mean that Portland stone is hard enough to stand up to weathering, but can easily be cut and carved by masons.
Stone was first quarried from the Isle of Portland in Roman times and used for buildings in nearby Dorchester. After the Great Fire in 1666, nearly all significant buildings in London were rebuilt using Portland stone, the most famous of these being St Paul’s Cathedral. And it was the material of choice for many homes constructed during the housing boom of the Georgian era. Until the arrival of the railways in the early 20th century, the use of Portland stone was restricted to areas within easy reach by water.
There are three different kinds of Portland stone, but all are characterised by a stylish creamy colouration which has greyish or brownish tones. An especially beautiful feature is the presence of different textures within the stone, courtesy of its oolithic origins. Since it can be so readily carved, features constructed from Portland stone possess a characteristic sculptural elegance. Plus its natural slip resistance has long made it the obvious choice for staircases and steps.
A glance at some of the UK news reports for early 2014 leaves no doubt of the significance of Portland stone for Devon railways. This has been true for Britain as a whole since Roman times: some of the country’s most important and beautiful buildings are constructed from this unique natural resource. Sculptural elegance coupled with weather- and slip-resistance make Portland stone the ideal material for stone steps in a business or domestic context. Contact London Stone Steps to benefit from a generation’s experience of working with Portland stone.