The rarest birthstone on the list of traditional birthstones is undoubtedly alexandrite. This stunning gemstone is highly sought after for its unique color-changing properties. Alexandrite is known for its ability to appear green in daylight and red under incandescent light. This natural phenomenon is caused by the presence of chromium in the gemstone’s composition.
The rarity of alexandrite is mainly attributed to its limited sources. The gemstone was first discovered in the Ural Mountains of Russia in the 1830s, and it quickly gained popularity among the Russian aristocracy. However, the Russian mines were soon depleted, and today, finding natural alexandrite of high quality and significant size is incredibly rare.
The scarcity of alexandrite has also resulted in its high cost. The price of this birthstone can vary greatly depending on factors such as color, clarity, and carat weight. Natural alexandrite with vivid color changes and minimal flaws can command exorbitant prices in the gem market.
Another exceptionally rare gemstone is the black opal. Opals are known for their iridescent play-of-color, but black opals are particularly coveted for their dark body color, which allows the play-of-color to stand out in a striking manner. These gems are mainly found in Australia, with Lightning Ridge being the most famous source.
Black opals are incredibly rare due to their formation process. They are formed in voids or cavities within ironstone, and the combination of iron oxide and carbon creates the dark body color. The scarcity of suitable opal-bearing rocks and the specific conditions required for the formation of black opals make them highly uncommon.
In terms of birthstones, some may argue that any gemstone can be considered rare if it possesses exceptional qualities such as clarity, color, or size. However, in terms of natural scarcity and market demand, alexandrite and black opals stand out as the most sought-after and rarest birthstones.
It is worth noting that rarity does not always equate to beauty or personal preference. Birthstones such as diamonds, rubies, and emeralds may be more commonly known and readily available, but they still hold immense value and significance to many individuals.
The rarest birthstone on the traditional birthstone list is alexandrite, followed closely by black opals. These gemstones are highly sought after due to their limited sources and unique characteristics. While they may come at a considerable cost, their rarity and beauty make them prized possessions for those lucky enough to own them.