gemstones captivate us, mainly because of their unique optical characteristics. Opals often exhibit a spectrum of colors called “play-of-color,” which is observed in various kinds of lighting. The Roman naturalist, Pliny the Elder, referred to opal’s play-of-color in the 1st Century A.D., when he wrote: “For in them you shall see the living fire of ruby, the glorious purple of the amethyst, the sea-green of the emerald, all glittering together in an incredible mixture of light.”

Opal is an October birthstone. Every opal is unique in appearance, which makes them desirable for anyone who craves individual expression.


Opals can have fiery play-of-color, but they can also be colorless, opaque, translucent or transparent.


Opals are mainly cut as cabochons or fashioned as beads. Opals are hardly ever faceted due to their soft nature.


The majority of the world’s precious opal comes from Australia, where it is the national stone. Other sources include Brazil, Ethiopia, Madagascar, Mexico and Peru.


Opal has a hardness of 5.0-6.5 on the Mohs Hardness Scale. Due to their relative softness, opals are rarely faceted.


Opals may be treated to enhance their color or appearance. Any treatments should be disclosed to the consumer.


The discovery of the ordered spherical structure of precious opal in the 1970s led to the possibility of lab-created opals. This information needs to be clearly disclosed to the buyer.

Care & Cleaning

  • To minimize scratching and wear, store each piece of fine jewelry separately in a soft cloth or padded container.
  • Opals should not be subjected to heat, chemicals, temperature and air pressure changes, because they are somewhat delicate.
  • The best way to clean opal jewelry is with warm, sudsy water and a tightly woven microfiber or other soft cloth. Always avoid ultrasonic machines and steam-cleaning.
  • Take all your fine jewelry to a professional jeweler at least twice a year for a thorough cleaning and inspection.

Find Opal pieces at a trustworthy, JA Member Jewelry store in our Find a Jeweler directory.

Content © GIA. Image © Robert Weldon/GIA

Find a JA Member Jeweler

Search our directory for reputable jewelers

Jewelers of America

In 1906, Jewelers of America was founded by jewelers for jewelers, with a desire to advance the professionalism and ethics of the jewelry industry.

Today, we continue that mission and Jewelers of America Members stand as the most trustworthy, informed and professional jewelry businesses within the United States.