This is a blue Chalcedony gemstone necklace. Chalcedony belongs to the quartz group of minerals. It was used in ancient times by Egyptians, Greeks and Romans for jewellery and its name may have been derived from the Greek City of Chalcedony. This necklace is most unusual because the stone has been cut into graduated pear-shaped Briolettes which is a beautiful and elegant faceted gemstone cut. The gemstones are on a 21 cm string ranging and from 10 to 20mm each sone. They hang from an attractive adjustable silver chain to allow it to be worn at a variety of lengths from 44.5 cm to 49cm.