Local History

Portland stone was formed millions of years ago during the Jurassic Age.

Its properties have made it a useful material in the construction of numerous buildings, including St Paul's Cathedral and Buckingham Palace.

And Portland stone's international reputation is one reason why the name 'Portland' pops up as place and street names all over the world.

Dorset is on a belt of limestone which goes all the way up through Bath and onward to Yorkshire, but the rock in each area has completely different properties.

Stone found in the Dorset area is strong, but also quite malleable and easy to cut.

The old-styled quarry

Portland stone is formed under a layer of rock called the Lower Purbeck Beds.

And to get hold of it, the stone has to be extracted.

Stage One: Bringing the stone to the surface

Portland stone is gathered by two different methods - quarrying and mining.

The quarry method is the one that has existed on the island for hundreds of years.

It involves digging up tons of overlying rock, and bringing the rock out using heavy equipment.

Wire saws carve out chunks, replacing the need for explosives and cutting down the time it takes to cut the stone out of the rockface.

Most of the area surrounding the quarry is covered with chunks of rock - and there can be up to a million pounds' worth of stone there at any one time.

Going underground

Portland's alternative method for excavating stone is through mining.

The Bowers mine was the first new mine to be opened in Britain for eighty years when it was unveiled in 2002 for tests, and now produces rock alongside the quarry.

Mark Godden is Mine and Quarry Manager

Mining the stone is regarded as more environmentally friendly then quarrying, as Mine and Quarry manager Mark Godden explained:

"We're not involved in moving huge volumes of overburden; that's the material which overlies the stone, which is essential in an open-quarrying situation, so we save a great deal of visual disturbance at surface. Nobody knows we're here."

Technology

The stone underground has to be carefully cut out of the rock, and new equipment is used which cuts out the slabs of rock by first dry-cutting through the rock horizontally.

This machine cuts the stone to size

The machine then slices down through the rock to create individual chunks, which helps the stability of the mine intact.

As he spends much of his working day underground, Mark says that safety is paramount:

"There are obviously issues with stability and health and safety, but we systematically rockbolt with three metre long bolts, we monitor incessantly, and so far everything is under control."

Lifting vehicles then take the rock from the mine up to the surface, where it is stored until it's needed.

Stage Two: At the factory

Once the stone has been brought to the surface, its life changes completely.

The Albion Stone factory on Portland uses the stone for totally different purposes depending on the order.

Stone is selected for a job depending on its size and weight. It is then taken to be cut to size using a powerful water-cutting machine.

Once the stone piece has been cut to specification, it is given a quality check and then sent off to be specially cut into particular shapes.

Ornate designs

For some of the more demanding orders, masons are given the job of carving and chiseling designs and patterns into the stone.

Stonemasons are skilled operators

The orders for the stone can range from old cathedrals to modern day shop fronts, with each different order requiring some intricate work from the masons.

Once the finishing touches have been made, the stones are sent to be packaged and delivered - but not before a final quality test is done.

Stage Three: Where to now?

Portland stone has been used to decorate some special places - among them the New London Stock Exchange, the Queen's Gallery at Buckingham Palace, London, and was also chosen for use in the British Memorial Gardens in New York, to commemorate the victims of the 9/11 attacks on the World Trade Centre.

So wherever you go in the world, keep an eye out for a little piece of Dorset.