Antique Blue John Sterling Silver Necklace Pendant Art Deco Cabochon Oval 1920s Bleu Jaune Womens Mens Rare Gemstone Jewelry Jewellery art deco earrings I'm not sure if it

I'm not sure if it is Georg Jensen but it certainly looks like their design

it's stubborn to clean off

Most of the enamel is present with some wear and bruising as to be expected with age and use

The item is stamped for "935" for silver

Antique Blue John Sterling Silver Necklace Pendant Art Deco Cabochon Oval 1920s Bleu Jaune Womens Mens Rare Gemstone Jewelry Jewellery art deco earrings I'm not sure if itDESCRIPTION: A petite antique art deco (c1920s) solid silver and genuine blue john mineral necklace pendant. The pendant is stamped "SILVER" on the rear. It weighs approx. 2. 47g and the size dimensions are in the later photos. Blue john is an extremely rare mineral and can only be found in Derbyshire in the UK (not far from me), it is in fact Britain's rarest mineral. The surface of the blue john has some natural fissures in it.