Swiss blue topaz, iolite and white topaz set in 18ct gold plated sterling silver or sterling silver. The belcher chain is adjustable from 16"/40cm to 19"/47.5cm.
The necklace represents the different shades of the sea. The necklaces are made by a jeweller, and the stones are stunning.
Seen here with the Azure pebble rings and the Azure pebble 3 stone rings.