The October 5 auction will centre on a collection of more than 250 lots of bowls, cups, vases, urns, cutlery and jewellery jointly assembled over the last decade by two avid collectors. Pieces date from c.1770 to modern times and are valued from £30 to over £30,000.
The semi-precious mineral - a unique form of fluorspar with bands of a purple-blue or yellowish colour - is found only at Blue John Cavern and Treak Cliff Cavern at Castleton in Derbyshire. Blue john became increasingly popular in the second half of the 18th century when it was mined for its ornamental value. Today, with mining occurring on a very small scale, it has become highly collectable.
One of the sale's stars is a c.1780 ormolu-mounted urn, right, attributed to the famed Birmingham industrialist Matthew Boulton. He championed the material, using it to create his trademark neoclassical-style ormolu vases, urns, candelabra and elaborate turret clocks.
Dates are yet to be confirmed, but highlights will be on display in London and Derbyshire including at Treak Cliff Cavern before the Birmingham sale.
