Opal – Birthstone of October
Opal is one of the most recognisable of all gemstones, treasured for its wide range or iridescent colours and textures.
It has been a popular choice for ornamentation and jewellery since classical times, but really came into its prime after the opening up of Australia, the source of over 90% of the worlds supply, to the wider global community.
Opal is the birthstone of the month of October, and inspired artists and writers a like with its fiery or galactic appearance. It also enjoys its place in many historical beliefs, such as that held by both Bedouins and some nations of First Australians, that opal was lightning or stars that had fallen from the sky during thunderstorms. In classical Greece, it was thought that opals could grant the gift of prophesy and protection from disease. In Europeans the gem was historically linked to purity, hope and truth.
Opal enjoys a range of beliefs surrounding matrimony. It is the stone most appropriate to celebrate a 14th wedding anniversary (replacing the previously popular but unethical Ivory). There is an old superstition that presenting an opal as an engagement ring is bad luck, unless of course, the bride is born in October.
Opal stone sold in jewellery is split into three types. Solids, doublets and triplets. Solids are the most valuable of these and are a complete, polished and cut gem. Doublets and triplets are compositions of thin slices of opal stone, an ironstone or other suitable base stone, and in the case of triplets, a clear plastic, resin or occasionally glass cap to help give the perception of depth.
Cleaning and Storage:
Opal is softer than some other precious gems, and the safest way to clean this stone is with warm and mild soapy water. Other cleaning methods might damage the opal or filler material. Be cautious that prolonged exposure to water or steam may weaken the adhesive in opal doublets and triplets. Any kind of opal can fracture if exposed to high heat or sudden temperature changes.
To prevent jewellery set with harder gems from scratching opal, store it by itself.
*Find out more about Opal and Australia by listening to the National Dinosaur Museum Podcast Echoees from the Eons.