Humans and crystals have been together for quite some time. The earliest records of crystals being collected by humans can be dated back to over 100,000 years ago. However, as technology improved, humans gained more information on naturally occurring crystals found beneath the Earth’s surface. 

As of now, there are over 200 known varieties of crystals and gemstones. Along with some of the most precious crystals, including ruby, diamond, and sapphire, there are numerous other crystals, and some of them are incredibly rare. 

This post looks at some of the world’s rarest crystals, in no particular order of rarity. 

Pink Star Diamond

This crystal is the rarest of the rarest when it comes to diamonds and it is one of the most valuable gemstones on the planet.

It is known for its extraordinary pink color and only a few of these have ever been discovered.

 

This diamond weighs 59.60 carats (11.92 gm). It was mined by De Beers in 1999 in South Africa and was sold for a record-breaking price of $71.2 million at an auction in 2017.

Tanzanite

Tanzanite is one of the most beautiful blue crystals, a variety of a mineral named zoisite; however, the crystal doesn’t get its name from the mineral. Instead, it is named after the location of its discovery which is a small area near the foot of Mount Kilimanjaro in Tanzania. So far, it is the only known source of the crystal, which makes it rare and extremely valuable. 

Since its discovery in 1967, the crystal has gained popularity among jewelers and gemstone enthusiasts. However, according to estimates, the reserves of this precious crystal would last for only 20 to 30 years before the supply deletes, which will make the stone significantly more rare and valuable than diamonds unless a new source is discovered.

If you look at the properties of this crystal, it ranks between 6 and 7 on Mohs’ scale of hardness which makes it ideal for everyday wear. Moreover, its highly prized blue color may closely resemble blue sapphire, a favorite crystal for jewelry. However, heat treatment can significantly enhance its blue coloration, making it more unique and strikingly beautiful. Since there is only one known source of the crystal, Tanzanite is a highly valuable crystal with an average per-carat price of $1,200 for top-quality crystals.   

Poudretteite 

Another extremely rare crystal is Poudretteite which was discovered during the 1960s by the Poudrette family at their quarry near Mount St. Hilaire in Quebec, Canada. The crystal was named after the name of the family that first discovered it. However, the crystal was not officially recognized as a new mineral until 1986. Hence for a long time, there were no reported discoveries of Poudretteite. 

Several decades later, a gem-quality specimen of the crystal was first documented in Burma. Since then, only very few crystals have been found. The crystal is so rare that clean crystals over 1 carat are hardly ever found. Moreover, the largest known Poudretteite weighs 9.41 carats. Since it’s very rare to find a crystal of this weight, the largest known Poudretteite sits at the Smithsonian National Museum of Natural History.   

Benitoite 

Benitoite, the state gem of California, is another rare crystal that is only mined in a small area of California near the San Benito River. Hence, the gemstone got its name Benitoite. The crystal was first discovered in the early 1900s by the geologist George D. Louderback.

However, it was not until 1985 that the crystal became the official gemstone of California. The major source of the rare crystal near the San Benito River was closed for commercial mining in 2006. While trace quantities of the crystal were discovered in Japan, Australia, and Arkansas, California is the only known source that allows feasible mining of the crystal, making Benitoite another rare crystal in the world. 

Benitoite has a deep blue color that shows unique fluorescence when caught under UV light. If you want to purchase this rare crystal, make sure you find a trustworthy and legitimate source. Moreover, you need to go for stones with a medium body tone and a cut that enhances the stone’s fire. Crystals that are too dark in color will not reflect the light well. Similarly, a color that is too light will have a washout-out appearance. Furthermore, you shouldn’t expect to find stones that are heavier than 3 carats. 

You can find a high-quality medium blue Benitoite with an average price of $3,800 per carat. Stones that are less than 1 carat will have a relatively much lower price. 

Black Opal 

Opals are usually creamish-white and can display rainbow-colored inclusions as light reflects on the stone. However, black opals are different and rare. Most of the black opals are mined in the Lightning Ridge area in New South Wales, Australia. Since it is extracted from a single source, black opals are the rarest of all opals found in Australia. 

Black opals have a naturally black body color. However, you can also find variations of the stone in green, blue, and brown colors. 

The most precious black opals are the ones with a darker color and brighter inclusions and the most precious black opal of all time is known as the “Aurora Australis,” which was found in 1938 in the Lightning Ridge area. The 180-carat black opal had an estimated worth of $650,000.  

Taaffeite 

Last on the list is another rare crystal, Taaffeite, which is also considered the rarest crystal globally. As of now, there are only 50 known specimens of this rare crystal, and most of them are held in private and geological collections. 

The crystal was discovered by chance by Austrian-Irish gemologist Edward Taaffe. Hence the crystal got its name. In 1940, the geologist bought a box of spinels, but he noticed that the mauve-colored spinel didn’t react to light in the same way as the rest of the spinels did; he sent it for further examination. The results revealed that the mauve-colored spinel was an unknown gemstone with no known source.

A few years later, Taaffeite was announced as a naturally occurring mineral. As a result, several other collectors re-examined their spinel collections and found a few more rare crystal specimens. Finally, the crystal source was tracked down, which revealed that most of the crystals came from Sri Lanka, whereas a handful was also found in China and Tanzania.

Conclusion

This brings an end to the list of the six rarest crystals in the world. There are several other rare crystals, such as Alexandrite, Padparadscha sapphire and many more that will hardly ever make an encounter with the general public, but they will continue to be rare and precious crystals that will be of immense value to people.