VINTAGE REAL SILVER & RARE BLUE JOHN GEMSTONE PENDANT & CHAIN

VINTAGE REAL SILVER & RARE BLUE JOHN GEMSTONE PENDANT & CHAIN This is rare Antique Victorian pear drop pendant mounted in real Silver with a real Silver chain. The pendant itself is real BLUE JOHN gemstone which is one of the rarest gemstones in the world. It displays the purple colour and zig zag banding that this gemstone is so prized for. The pendant measures 4 cms or 1 1/2 inches long. The Sterling Silver chain measures 50 cms or 20 inches long and is a later replacement for safety and esthetic reasons. It is in the good Antique condition as shown, please study my pictures. Below is a description and history of this rare gemstone. Blue John Stone is a rare, semiprecious mineral found at only one location in the world - a hillside near Mam Tor, just outside Castleton , in the Derbyshire Peak District National Park, England. The name Blue John derives from the French Bleu Jaune meaning Blue Yellow. It is a form of fluorite and was discovered as miners were exploring the cave systems of Castleton for lead. Nowadays, the caves of Castleton are magnificent show caves and are some of the most popular tourist attractions in Derbyshire. Of the four show caves only Treak Cliff and, to a lesser extent, Blue John have veins of Blue John Stone. Treak Cliff Cavern still mines about 500 kilograms of Blue John Stone each year. The veins of Blue John Stone are easy to see and many of the formations are well lit. Blue John Stone is a semiprecious stone and gives Castleton its nickname of 'Gem of the Peaks'. Chemically, Blue John is calcium fluoride (CaF 2) which has been coloured by films of oil deposited on the crystals millions of years ago. Although it is known as fluorite the old miners, referred to it as fluor spar (sometimes spelt fluorspar). Fluorite often forms in cubic and octahedral crystals and is usually grey, yellow or purple in colour. Fluorite used to be mined mainly for iron smelting but now has many other uses including toothpaste. The form of fluorite unique to Castleton is banded purple and yellow or grey and is known as Blue John. Banded Blue John fluorite has been worked into ornaments since 1750 and there are about 14 categories of banding patterns . Blue John has been prized for ornaments and jewellery and it can be found in many great collections housed in places such as Windsor Castle, the White House and the Vatican. * PLEASE NOTE THAT MY POSTAGE COSTS ARE EXACTLY WHAT THE ROYAL MAIL CHARGE ME AND I MAKE NOTHING ON PACKING OR POSTING. **** I DO COMBINE POSTAGE COSTS FOR MORE THAN ONE ITEM WON SAVING BUYERS MONEY. ITEMS SHOULD BE PAID FOR WITHIN 5 WORKING DAYS AFTER THE END OF THE AUCTION UNLESS WISHING TO COMBINE IN WHICH CASE PLEASE GET IN TOUCH. THANK YOU FOR YOUR INTEREST AND FOR VIEWING MY AUCTION. read more