A Bluejohn (Derbyshire spar) mineral display piece comprising an irregular block with flat upper face, smaller pyramidal shard and base metal figure of a miner swinging a hand-tool. 220 grams total, 73mm (3"). Property of a Walton on Thames gentleman; previously acquired on the UK art market. Blue John is a semi-precious form of fluorite with bands of a purple-blue or yellowish colour, found at Blue John and Treak Cliff Caverns near Castleton, Derbyshire, UK. [No Reserve]