Blue John or Black Jack?

Let’s start at the beginning: where does the name ‘Blue John’ come from? The traditional story is that the French named it bleu-jaune, meaning ‘blue-yellow’ when it was exported to France during the second half of the eighteenth century. Another theory is that the English miners who were extracting the mineral first thought they uncovered ‘Black Jack,’ a term used for the zinc mineral sphalerite. Once they were out of the mines and in the sunlight, they correctly identified the material and adapted the name to Blue John. No matter which story you believe, the mineral fluorspar that we now call Blue John is one of most decorative and precious materials found on eighteenth and nineteenth century furniture and decorative arts.

It is worth noting that Blue John is not always blue–in fact, it can be almost any colour, including white, cream, yellow, or purple varieties. Often times the mineral takes on a rainbow-like effect with various colours forming bands that bleed into one another.

One of the most curious facts about Blue John is its origins: the mineral is found only in Derbyshire at the Blue John Cavern and Treak Cliff Cavern in Castletown. When discovered in these mines in the eighteenth century, the material quickly became highly prized for its aesthetic value and its rarity. One of its first recorded uses for decorative purposes was for the borders of a chimney-piece supplied to Nathaniel Curzon Bt., 1^st Baron Scarsdale in around 1761 for Kedleston Hall in Derbyshire under the supervision of Robert Adam. In the 1770s, Matthew Boulton also championed the natural beauty of the fluorspar, using it frequently in his wonderful vases and perfume-burners, often further enriched and embellished with ormolu mounts. Its use was further promoted throughout the 19^th century by William Spencer Cavendish, 6^th Duke of Devonshire and his son William Cavendish, 7^th Duke of Devonshire – and many ‘Blue-John’ objects can be see in the Devonshire Collections at Chatsworth.

An Exceptional Blue John and Ashford Marble Table, Mackinnon Fine Furniture Archive

One of the most impressive examples of the mineral used in decorative arts is this superb table made of Ashford marble and inlaid with the finest specimens of Blue John. The black marble is also local to the area, and was extracted from the ground at Ashford-in-the-Water, and provided a wonderful dark contrast to the vivid colours of the Blue John, once mounted. Demand for Blue John was high, having been popularised by the aristocrats, and followed quickly by the tourists to the area. A number of local craftsmen set up business producing objects of Blue John, of Ashford marble, and of course of combinations of the two. In the 19^th century, this included S. Birley of Ashford, Thomas Woodruff, Tomlinson of Bakewell and R.G. Lomas of Derby.

Thomas Woodruff in particular started a business in Bakewell in 1842, and was described as ‘Inlayer, and Worker in Marble’, ‘Black Marble Inlayer’ and ‘Black Marble Worker’. By 1857, he had moved to Buxton and referred to himself as a ‘petrifactioner’ – selling of fossils, mineral specimens, marble and of course ‘Blue John’ to the thriving tourist trade in Buxton. His name had been firmly established in 1851 when under the patronage of the Prince Consort, he had exhibited two inlaid tables at the Great Exhibition.

Blue John is most commonly seen in smaller items, including decorative pieces such as goblets, bowls, cassolettes, and obelisks. Here are a few pieces from our archive, which are magnificent examples of the range of colour, form, and style of Blue John in art.