Blue John is a rare variety of fluorite found almost exclusively in Derbyshire, England, particularly around Castleton in the Peak District. Celebrated for its striking bands of purple, blue, yellow and cream, Blue John has been used since the eighteenth century to create vases, urns, candlesticks, table tops and decorative ornaments. Genuine antique Blue John is highly sought after due to the scarcity of the material and its distinctive natural beauty.