Antique early 19th century George III Derbyshire Spar or Blue John urn mounted as a table lamp. The solid stone displays wonderful color. Lamp measures 22 1/2" tall to top of finial; 11" tall to top of stone vase x 4 3/4" diameter. Good condition - scattered chips and loss from age; typical fissures. Displays beautifully. Blue John is a semi-precious mineral, a rare form of fluorite with bands of a purple-blue or yellowish color. In the UK it is found only at Blue John Cavern and Treak Cliff Cavern at Castleton in Derbyshire. During the 19th century, it was mined for its ornamental value.