Blue John Fluorite Pendant, Oblong Cabochon, 925 Silver, r4Blue John Rainbow Fluorite Pendant 925 Sterling Silver Blue John is a Fluorite variety that is found only in Derbyshire, UK. First discovered by the Ancient Romans, 2000 years ago, so much has been mined since that it has become quite rare. The name derives from the french ' bleu y jeunne ' meaning blue and yellow which are common colours for this stone. Blue John is often found in small nodules so the colours and bands often appear to radiate from a