Ashford Black Marble

Ashford Black Marble is the name given to a dark limestone, quarried from mines near Ashford-in-the-Water, in Derbyshire, England. Once cut, turned and polished, its shiny black surface is highly decorative. Ashford Black Marble is a very fine-grained sedimentary rock, and is not a true marble in the geological sense. It can be cut and inlaid with other decorative stones and minerals, using a technique known as pietra dura. Derby Museum has a diagram of Ecton Hill made from Ashford Black Marble and other minerals.

The decorative uses of the local black mineral have been found in prehistoric finds, but the first recorded customer was Bess of Hardwick in 1580.

Henry Watson, the uncle of Derbyshire geologist White Watson, is regarded as one of the key figures in the development of the local industry of inlaying Ashford Black Marble in the 1750s. He owned a water-powered mill at Ashford in the Water.

There was a thriving trade in the manufacture of urns, obelisks and other decorative items from Ashford Black Marble during the late 18th and early 19th century. John Mawe had a museum in Matlock Bath that dealt in black marble and Ann Rayner engraved pictures, next door at another museum, on black marble using a diamond. Many fine examples of engraved and inlaid black marble exist in local collections, including those of Derby Museum, Buxton Museum, and Chatsworth House. In 2009 huge blocks of unworked Ashford Black Marble were unearthed during excavation work near to the Seven Stars public house in Derby. The plan was to auction them due to the rarity of unworked Ashford Black marble. It was speculated that the rocks had been abandoned when an Ashford Black Marble manufacturer moved in the 1880s.

Although referred to as marble, the rock is of purely sedimentary origin. It is a dark, fine-grained, muddy Carboniferous limestone, rich in bitumen which gives it its dark grey colouration which turns a glossy black when polished and surface treated. The prime source of this rock was from Arrock Mine, and later in 1832 from nearby Rookery Plantation, near Ashford-in-the-Water.

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