Onyx is formed of bands of chalcedony and can be found in various regions of the world. It has a long history of being used for jewellery and carving with some pieces dating from as early as the Second Dynasty in Egypt. Please remember our semi-precious beads will all include natural inclusions and slight variations of colour. Of course this makes them even more unique as no two semi-precious beads are exactly the same. Approximately 80cm String.