Interesting facts about opals --- Fun, weird, tidbits.

Opal is one of the most precious and absolutely breathtaking gemstones in the world. It’s full of mystique, allure, and heart-stumping beauty. Not only that, but it’s also one of the most interesting and history-rich stones on the market — in the present and the past. Join us as we slip into professor mode and give you some of the most interesting facts about opal. Facts, tidbits, and quiz night answers you didn’t know. Get ready for your Jeopardy cheat sheet on opal.

Interesting facts about opal

Hydrated Amorphous Silica

From 3 to 20% of opal’s content is water. It is an extremely water-rich gemstone that due to this mixture of liquid and rock obtains its unique and very divergent colors. 

It’s mostly found in fissures

Most opal deposits are uncovered in relatively low-temperature fissures in almost all kinds of rocks among them are sandstone and ironstone.  It’s within these rock types, respectively, where magnificent pipe opals and boulder opals, like the boulder opal in the Regalia Ring, form over millions of years.

There are 3 types of opals sold on the market

  • Precious opal, which displays a unique iridescence. This is a flash of color or spectrum burst of colors similar to a rainbow that occurs when a fixed source of light strikes certain minerals. 
  • The second type of opal is called common opal —- these are gemstones with have a fixed hazy-milky-turbid sheen and typically lack bold color play. 
  • Synthetic opal, first created by Pierre Gilson in 1974, this type of opal is created in labs and sold commercially. The lab-created opals and are mostly used for scientific developments, the study of photonics, and in the cosmetic industry. 

Cleopatra’s favorite

Back in the days of the great Empire, opals were more valuable than gold. The gemstone was one of Cleopatra’s favorites and rumor has it that Marc Antony would constantly shower her with them — having them brought from the Roman frontier in Slovakia.

From deep space

Many early opal traders believed that the gemstone came from space and was lined with cosmic heavenly properties. Oddly enough that idea brings us to the next big-ticket item when it comes to opals.

Opals on Mars

A special kind of opal can be found on Mars' surface. What makes this such an interesting find? Aside from the fact that it’s a space rock, an actual space rock, this particular kind of opal can help in finding life outside of our planet.

Alien opal

The meteorite Nakhala, held in the Natural History Museum of London, could hold the record of ancient Martian life. The known traces of fire opal detected within the meteorite were investigated by a research team from the University of Glasgow and what they discovered was a game-changer. These opals, like the same of their kind, found on Earth, form around hydrothermal vents on the seafloor. They have, due to how they are geologically constructed, the ability to trap microbes. This means that the best chance of proving, right now, that Mars was once inhabited by life could be found in the red planet’s opal depository. 

Australia is the main mining source

Australia holds a huge monopoly on the opal trade. More than 95% of the world's supply comes from the land down under. The rest is split between Brazil, Mexico, Ethiopia, and boutique miners in the western parts of the USA. 

Opal and Chakras

Due to their various color and nature, opals are used in various tantric and new-age practices. Amongst those to stimulate and help Chakra points. 

Opals are fragile

The Mohs scale ranks gemstones according to their toughness, their hardness density. Opals are generally brittle and require more caution when handled according to this scale.

October is opal’s month

Opals is the official birthstone of October. Each month has a birthstone related to it, and in ancient times it was a tradition to give people born in this month that stone. Most believe that opal became the official stone of October during the Roman empire, more precisely during Octavius' reign. 

The etymology of opal

The word opal comes from the Latin word “opulus” which is loosely translated as "precious stone."

Wood and opal

Did you know that petrified wood has the same makeup as opal? That’s right - they are both framed from amorphous silica. To what extent is this similarity? To the extent that certain petrified woods are in fact considered opal.  You may hear these specimens referred to as opalized wood or wood replacement opal.

Biggest opal

One of the biggest opals ever found was discovered by miner Charlie Dunstan in November 1906. It was huge by opal’s standard, The stone was eventually bought in the early 1940s by none other than the J.D. Rockefeller. It is called “the Fire Queen.”

Black Opal

Black opal is considered to be the most valuable kind of this gemstone available. This is due to how rare it is compared to white, gray, and green opal.

The most valuable opal

The “Aurora Australis'' is considered to be the most valuable black opal in existence. It was also discovered by opal miner Charlie Dunstan in 1938 in Lightning Ridge. The stone is now on display at the Altman and Cherney showroom in Sydney, Australia. 

Natural state

Unlike other gemstones in the market, opals are generally left in their natural state. Some common treatments are performed on them but it’s mostly to fill in fractures or darken the stone. 

The goddess of fertility

One of the first references to the gem was made by Pliny the Elder. The man suggests that the real etymology of the stone is attributable to the wife of Saturn, Ops —- the goddess of fertility. 


In the Middle Ages, opal was considered to be a stone that could ward off the Devil and call on angels. As such it was said to provide great luck

Anne Of Geierstein 

Opal had a fall from grace when Sir. Walter Scott published the novel Anne Of Geierstein in 1829. In the novel, the Baroness of Arnheim wears an opal talisman with supernatural powers. When a drop of holy water falls on the gemstone, the opal loses all its worth and the Baroness dies soon after. Sales of opal dropped by 50% across Europe due to this novel — and it even led to Russians labeling opal as the embodiment of the “evil eye.”


Opal & Ruby Ring
Regalia Gold Opal and Ruby Ring from NIXIN

Here at NIXIN Jewelry, we are drawn to uniquely beautiful opals and the interesting stories they hold.  Come explore the magic. 


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