Blue John Cavern
...unique and mysterious
The Blue John Cavern is one of four show caves in the Castleton area of Derbyshire. The semi-precious mineral 'Blue John' or 'Derbyshire Spar' is mined from this cave.
Although the cavern works as a show cave, the mineral is still worked here during the winter months. The miners who work the remaining seams act as guides for the underground tours.
Blue John is a blue/purple and white/yellow banded variety of fluorite found only here and at the nearby Treak Cliff Cavern. However, blue fluorite occurs widely throughout Derbyshire and especially in the Ashover and Crich areas.
The Cavern Tours are of enormous educational interest showing plainly how the caverns are formed in limestone strata and how the limestone itself had much earlier been formed by the deposits on the floors of great oceans which have long since receded, as the fossilised remains of marine animals now show.
The Cavern is well illuminated by electric lighting. Very thorough planning was necessary here to ensure that the whole project was complementary to the caverns as a whole, without appearing to intrude or commercialise the caverns in any way. It has been suggested that the Blue John Cavern is the finest that can be seen by the general public in Western Europe.
There is also a craft shop with a wide variety of Blue John jewellery set in silver and gold, alongside Blue John Ornaments such as bowls, eggs, and goblets.
Visit the Blue John Cavern website for details of opening hours and admission prices.
Last Updated: 28 Apr 2015