Investment, technology and a local workforce.

Gallagher's continued investment ensures a sustainable future.

Hermitage Quarry is the first Ragstone quarry in history to be worked to modern standards. This is particularly demanding due to the nature of the geology of the ‘Hythe Beds’, so called because they outcrop in the cliffs at Hythe. They run westwards through Kent into Surrey and from the Greensand Ridge. Maidstone and Sevenoaks sit on Ragstone and the villages of Sutton Valence and Wateringbury are on the top of the ridge, above the Weald of Kent.

Ragstone occurs in bands between 15cm and 60cm thick, alternating with a loose material called Hassock. These are much the same thickness as the Ragstone and the quarry face is striped, rather than a deposit of just mass limestone. To make quality products the Ragstone has to be separated from the Hassock. After crushing, screening and grading there are more than sixty products available at the quarry, including high quality aggregates and sand for the production of ready mix concrete.

2010 heralds 20 years of excavating at Hermitage Quarry which started in an area that had never been quarried before. Modern geological mapping shows it to have been the best area in the Hythe Beds, which vary in depth from east to west, with the best deposits in the Maidstone area.

The quarry is worked to an overall plan that enables it to be progressively restored using some imported inert material as a filler, to be returned to agricultural land and woodland after quarrying.

The main products are for the construction industry for road building, ready mix concrete and engineering work, although the traditional uses of Ragstone still remain. Gallagher’s landmark office park, Eclipse Park, near Maidstone, and the new headquarters building for Rolex at Kings Hill recently used concrete made from Ragstone from the quarry in its framework to maintain the integrity of the local environment. Stone for the repair of historic Ragstone buildings is a relatively small but very important demand, Gallaghers would like to encourage the greater use of Ragstone in new building projects.

Large blocks of stone are regularly used for sea defence works.

A request for help from the Olympic Park project has seen the quarry supply cut and dressed Ragstone blocks, with the assistance of local stone masons, to match and repair the walls of the River Lee.

One of the major advances at Hermitage Quarry, besides the increase in Ragstone based products, has been the use of the Hassock. With the benefit of major capital investment in the most modern and up-to-date plant and machinery and employing innovative new techniques this is now washed and used in such areas as drainage materials and pipe bedding as well as other specialist products. Whereas up to 70% of the quarried material in the Hythe Beds was once wasted, Hermitage Quarry has now reduced this figure to below 10%.

This is a critical step in ensuring that the quarry is a sustainable option with the least amount of waste possible and the very best use of fossil fuel used to produce the products that leave the quarry.

Gallagher Aggregates also operate Blaise Quarry at West Malling. The stone here is of a poorer quality and can only satisfy a small proportion of local demand for low grade aggregate. The increasing local demand for high quality material just cannot be met from the Blaise source.

As the only significant hard rock quarry in South East England, Hermitage is superbly located to supply the industry in one of the UK’s highest concentration of construction projects. Being local obviously means less fuel is used to deliver the quality products to construction industry.