Birthstones are intrinsically linked to sentiment and celebration, serving as personalized tokens of remembrance for birthdays and anniversaries since the late 1800s. While each gemstone within the traditional monthly chart possesses its own unique beauty, certain stones command significantly higher values due to exceptional color, quality, and scarcity. Price ranges can vary dramatically, but understanding the factors contributing to a birthstone’s cost provides valuable insight for both enthusiasts and prospective buyers. This article will explore the most expensive birthstones, detailing the characteristics that elevate their value and examining their historical significance.
A History of Birthstone Significance
The practice of associating gemstones with specific months has evolved over centuries. While modern birthstone lists are standardized, their origins are rooted in ancient traditions and evolving beliefs. The connection between gemstones and the zodiac was prominent in ancient cultures, with each sign believed to be influenced by a particular stone. These associations gradually shifted towards a monthly system, though variations existed for quite some time. The standardization of birthstones largely occurred in the early 20th century, solidifying the tradition of gifting gemstones based on birth month.
The Most Expensive Birthstones: An Overview
The most expensive birthstones are not simply determined by their aesthetic appeal, but by a complex interplay of geological rarity, desirable qualities, and market demand. Diamonds, rubies, and alexandrite consistently rank among the highest in value, followed by tanzanite and other exceptional gemstones. The following sections will detail each of these stones, outlining the factors that contribute to their price.
Diamond: The Apex of Value
Diamonds, the birthstone for April, are widely considered the most expensive birthstone. This high value is driven by a confluence of factors, including high market demand – particularly for engagement rings and luxury jewelry – exceptional hardness and durability (rated 10 on the Mohs scale), remarkable brilliance, and enduring cultural symbolism representing eternal love, purity, and wealth.
The price of a diamond is heavily influenced by the “Four Cs”: carat, cut, clarity, and color. Colorless diamonds, graded D through F, with Internally Flawless clarity, and Type IIa purity are the most coveted and command the highest prices, ranging from $3,500 to $10,000 per carat. Type IIa diamonds are particularly rare, being free of nitrogen and boron impurities. However, “fancy color” diamonds – those exhibiting hues like red, green, purple, orange, pink, and blue – can be even more valuable than their colorless counterparts due to their increased rarity. The intensity of color, graded by the Gemological Institute of America, directly impacts the price, with “Fancy Intense” and “Fancy Vivid” diamonds fetching the highest sums. The Pink Star, a 59.60-carat oval-shaped fancy vivid pink Type IIa diamond, sold for $71.2 million at auction in 2017, representing the world’s most expensive diamond ring.
Alexandrite: The Emerald by Day, Ruby by Night
Alexandrite, one of June’s birthstones, is often cited as the most expensive birthstone, surpassing even diamonds in per-carat price, ranging from $15,000 to $70,000 per carat. This exceptional value stems from its remarkable color-changing properties. Alexandrite naturally shifts from a bluish-green hue in daylight to a purplish-red shade under incandescent light, leading to the descriptive moniker “emerald by day, ruby by night.”
The gemstone was first discovered in 1830 in the Ural Mountains of Russia, coinciding with the birthday of Czar Alexander II, to whom it was named. Its red and green hues also mirrored the colors of the Russian military, solidifying its status as the national stone of Russia. Today, alexandrite remains exceptionally rare, contributing to its high market value.
Ruby: A Stone of Passion and Prestige
Ruby, the birthstone for July, holds the position of the third most expensive birthstone, with prices ranging from $3,000 to $12,000 per carat. As one of the “Big Three” precious stones – alongside emerald and sapphire – ruby is highly prized for its vibrant red color. Ruby and sapphire both belong to the corundum family, with color being the primary differentiator.
A gemstone must exhibit a dominant red hue to be classified as a ruby; reddish-orange stones are considered orange sapphires, while reddish-purple stones are classified as purple sapphires. The depth and saturation of the red color significantly impact the value, with deeper, more vivid reds commanding higher prices.
Tanzanite: A Recent Discovery with Rapid Appreciation
Tanzanite, one of December’s birthstones, has experienced a significant increase in value since its discovery in 1967 in the Merelani Hills of northern Tanzania. This gemstone, a transparent variety of the mineral zoisite, displays a beautiful blue or violet color when heat-treated. Uniquely, Tanzania remains the only source of tanzanite globally.
Tiffany & Co. introduced tanzanite to the market in 1968, naming it after its country of origin. The gemstone’s value is determined by color saturation, with deeper violetish-blue to bluish-violet hues being the most desirable and expensive, costing up to $1,500 per carat. Larger tanzanites, weighing over five carats, also command higher prices. In 2024, artist Naomi Sarna unveiled a 703.4-carat tanzanite sculpture, named L’Heure Bleu, breaking the record for the largest cut tanzanite.
Understanding Gemstone Hardness and Durability
The longevity and luster of a birthstone are directly related to its hardness and durability. The Mohs scale is used to grade gemstones based on their resistance to scratching and damage. Diamonds and sapphires are among the hardest birthstones, with ratings of 10 and 9 respectively, while pearl, another June birthstone, is among the softest, with a rating of 2.5. Opal, the October birthstone, also exhibits relatively low durability with a Mohs hardness of 5.5.
Birthstone Hardness Comparison
| Birthstone | Mohs Scale |
|---|---|
| Diamond (Apr.) | 10 |
| Sapphire (Sept.) | 9 |
| Ruby (Jul.) | 9 |
| Alexandrite (Jun.) | 8.5 |
| Topaz (Nov.) | 8 |
| Pearl (Jun.) | 2.5 |
| Opal (Oct.) | 5.5 |
Conclusion
The world of birthstones is a fascinating intersection of geological rarity, historical lore, and cultural significance. While all birthstones possess inherent beauty, certain gemstones – diamonds, alexandrite, ruby, and tanzanite – command significantly higher values due to their exceptional qualities and limited availability. Understanding the factors that contribute to a birthstone’s price allows enthusiasts and buyers to make informed decisions and appreciate the unique value of these treasured gems. The enduring popularity of birthstones demonstrates their continued relevance as sentimental gifts and enduring symbols of personal connection.