PLEASE NOTE: The blue john doublet has fogged due to condensation, see photos/video. I've altered the price accordingly. DESCRIPTION: A lovely genuine vintage sterling silver and genuine blue john doublet ring. Blue john is an extremely rare mineral and can only be found in Derbyshire in the UK, it is in fact Britain's rarest mineral. The ring sizes at approx. UK O.5 or US 7.5 and weighs approx. 2.90g and is stamped "SILVER".
