Our sterling silver October birthstone bracelet displays a fiery opal gem set in a simple polished surround on a fine adjustable chain. Each month of the year is associated with a different gemstone which brings luck to the wearer. The birthstone for October is Opal. Beautiful, precious opals are unique gemstones, famous for their shimmering display of colours. Multi-chromatic flashes of colour appear and disappear as the stone is moved.