DESCRIPTION: A vintage sterling silver and genuine blue john necklace pendant. The pendant is hallmarked for sterling silver, dating to 1981. It weighs 1.71g and the size dimensions are in the later photos. The blue john is very dark purple in colour, it looks almost black, see pictures/video. Blue john is an extremely rare mineral and can only be found in Derbyshire in the UK (not far from me), it's in fact Britain's rarest mineral.
