What is Blue John?

What is Blue John?

Blue John is now a very rare and mysterious gemstone mined around the Peak District village of Castleton, Derbyshire.

It is believed that it was the Romans that first discovered the gem some 2000 years ago and instantly fell in love with it's unique qualities.

What's its History

The Blue John mines were first discovered around 1750 in Treak Cliff, just outside Castleton, Blue John very quickly became popular for use as a decorative ornament.

Within ten years there were sixteen mines working the area to supply thirty-odd local firms who fashioned it into fireplace and other ornaments for the stately homes of England.

Goblets, urns, bowls, obelisks, clocks, paperweights, chalices and pyramids were all created from the distinctive Blue John. No two pieces look totally identical thanks to the colour variations in the stone. It was also used to create decorative stained-glass window panels, an example of which can be seen in Buxton Museum & Art Gallery.

The earliest dated example of decorative Blue John from Castleton is from 1762 in Kedleston Hall, near Derby, where there are Blue John panels mounted in a marble fireplace surround designed by Robert Adam.

The Blue John love affair lasted until the end of the Victorian era, but by that time whole Peak District industries were dependent on it and so another use needed to be found. It continued to be mined but instead of being used for decorative ornaments it was used as a flux in the steel industry.

Today there is very little Blue John waiting to be harvested, and although it is still mined during the winter months in Castleton, only small pieces suitable for jewellery are found.