One of the most interesting of all colored gemstones is our birthstone-of-the-month for October: opal. The type most people are familiar with is often imbued with an array of fascinating color plays, unmatched by any other natural stone — as well as a lingering veil of superstition — which, sad to say, just won’t quit. “Opals are bad luck!”

Utter nonsense! But let’s not get ahead of ourselves — first and foremost, we need to understand what we’re dealing with.

The material itself (a hydrated amorphous form of silica) is found in many areas of the world, but the vast majority of gem-quality opal comes from Australia, with almost all of the very finest quality material (“black” opal) mined in an area called Lightning Ridge. (Opals are also found in Ethiopia, Peru, Mexico, Brazil, Canada, Turkey, Hungary, and even in Oregon, Nevada and Idaho in the United States). Pricing has a dramatic range, from a few dollars per carat for low- quality common opal to many thousands of dollars per carat for fine black opal.

Opals can display any color (or combination of colors) imaginable, while some may be a single color such as white (“milk” opal), orange, blue, or even almost completely clear (“water” opal). Most gem-quality opals are cut as a cabochon (smooth dome-shape), although orange-colored Mexican “fire” opal (sometimes called “Tangerine” opal) may be found as faceted stones.

Synthetic (or more accurately, imitation) opals (first produced in the early 1970’s) are available at a fraction of the cost of genuine opals, but like most other synthetics, they have literally no “after-market” value. Opal “doublets” are often available, which feature a thin layer of opal that has been backed with a darker material (such as black onyx, obsidian or ironstone) to make the colors stand out more easily. Opal “triplets” are doublets that also have a clear layer of quartz or plastic over the top for protection. (Both doublets and triplets are relatively inexpensive.)  

Joe Brandt

The construction of the material is unique among gemstones, and opals may feature up to 10% water content, which can make them particularly susceptible to breakage from extreme temperatures or quick temperature changes. It is also possible for opals to dry out over long periods of time (resulting in internal fracturing or “crazing”), although most opals sold in fine jewelry stores today are stabilized. Because of their structure, it is inadvisable to subject opals to very high (or very low) temperatures, so an unheated attic may not be a good place to store opal jewelry. Because the hardness of opal is among the lowest of all non-organic gemstones, extra care must be used when wearing opal rings (or bracelets), as these are most prone to being damaged. Cleaning may be done carefully, using a soft brush — but opals should never be immersed and allowed to soak in a jewelry cleaner for any period of time — and ultrasonic cleaning is definitely a no-no.

The first recorded use of opals was in ancient Rome, at which time opals were given only positive attributes, but as far as “bad luck” stories go, opals have been subject to superstitions — kept alive mainly by folklore and disgruntled diamond traders — for the past several hundred years. As we entered the age of reason and science, these beliefs were largely buried, but in some corners of the world (notably certain areas in southern Europe and the Middle East), many jewelers won’t carry opals — and their customers wouldn’t buy them if they did. No gem has been more vilified than opal. Medieval Europeans dreaded the opal because of its likeness to the feared “Evil Eye,” with its superficial likeness to the eyes of cats, toads, snakes, and others.

In Sir Walter Scott’s popular 1829 novel, Anne of Geierstein, an enchanted princess wore an enchanted opal adornment in her hair, and the stone changed color to reflect her moods and tempers. At the end of the story, holy water sprinkled on the opal put out its fire — but as a result, the lady perished. There was also the rather gruesome tale of the Royal Stone-Setter who managed to break a King’s prized opal while attempting to set it into a piece of jewelry for the Queen. The King was so angry that he had the poor man’s hands cut off! (Definitely bad luck for the stone-setter!) As we entered the age of reason and science, these beliefs have largely been buried, but at least some of the superstitions still survive to this day, and strange as it may seem, there are those who still believe that it is bad luck to wear an opal if it isn’t your birthstone. I can confidently guarantee that this is not the case — unless, of course, you happen to be walking under a ladder and watching a black cat cross your path while wearing one!

Although opals have fallen in and out of popular use over the centuries, the undisputed fact is that they are among the most fascinating of all gemstones. Your jeweler should be able to show you some of the differences that exist between the various varieties of opal, and answer any questions you may have regarding this fantastic gem.  


Joe Brandt is a local resident, and president of J.L. Brandt Company, offering diversified fine jewelry advisory services to the general public since 1928. Readers are invited to submit questions or comments to [email protected] Names or contact information will not be used for publication, and all inquiries will be answered promptly.