One of December’s birthstones, Tanzanite is the quintessential haute‑fashion gemstone of the 20th century. Frequently synonymous with velvety blues, Peacock Tanzanite’s captivating fusion of hues offers a uniquely beautiful twist on a celebrated gem. Undeniably rare, its mesmerizing, all‑natural cocktail embodies the peacock’s dance of colors. Optimally oriented to reveal a shifting palette, Peacock Tanzanite glows with individuality at every turn. Solely from Tanzania, it is defined as much by genuine rarity as beauty. Discovered in the late 60s, Tanzanite mining is ostensibly over, leaving connoisseurs dependent on diminishing vaulted reserves.
Hardness 6.5 – 7
Refractive Index 1.691 – 1.700
Relative Density 3.35
Enhancement None
Beauty
Given its high transparency and an absence of inclusions are defining characteristics of Tanzanite, color and lapidary quality primarily determine its value. Thanks to its distinctive pleochroism (specifically, trichroism), where colors and intensity shift when viewed from different angles, Peacock Tanzanite displays a gorgeous bicolor-blend of purplish-blues/bluish-purples and greens, with a highly desirable medium saturation (strength of color) and tone (lightness or darkness of color), the marketplace ideal. The intensity of Peacock Tanzanite’s defining hues can also appear slightly different depending on the viewing angle due to its trichroism, while maintaining beauty in both natural and incandescent lighting, an exceptionally rare gemological ideal.
Tanzanite is a challenging gemstone for cutters due to the orientation of its trichroic crystals, which reveal three distinct hues: blue, purplish-red, and greenish yellow‑brown (bronze). The quality of faceting is critical, as the visibility of trichroism depends largely on cutting. Most Tanzanite is heated to permanently enhance its color by minimizing bronze tones and maximizing blues, purples, and violets. However, this process depends on the natural characteristics of each crystal and does not produce consistent results. While the rarest and most valuable color is a strong daylight sapphire‑like blue, most Tanzanite reveals a captivating interplay of its three trichroic hues.
Unlike most Tanzanite gems cut to minimize trichroism, unheated Peacock Tanzanite is deliberately oriented to maximize it, coaxing a luminous intermingling of colorful blues and greens. Notoriously difficult to cut, each Peacock Tanzanite crystal was optimally faceted in the legendary Indian gemstone city of Jaipur, home to some of the world’s very best Tanzanite cutters, and renowned for its master lapidaries. Each gem was carefully oriented to maximize the brilliance of its signature color combination, achieving a mirror‑like polish (accentuating its vitreous glassy luster), an attractive overall appearance (outline, profile, proportions, and shape), and eye‑clean clarity (the highest clarity grade for colored gemstones, as determined by the world’s leading gemological laboratories).
Tanzanite that is too large or poorly cut will darken, losing brilliance. Most popular and practical for jewelry are gems under 20 carats, typically fashioned into ovals and cushions, though rounds and other shapes are also available. Tanzanite also exhibits a color shift, where hues close on the color wheel change, moving from blue in daylight to purples and violets under incandescent light. Even its finest pure blues reveal violet undertones in candlelight. Color and size are linked, as richer, more intense hues are generally not found in smaller sizes. Tanzanite’s deeper, more expensive colors are often identified by quality prefixes such as ‘AAA’.
Enormously popular and one of the world’s bestselling gemstones, Tanzanite joined Turquoise and Zircon as December’s official birthstones in 2002. A variety of the mineral Zoisite, Tanzanite was christened by Henry B. Platt, Former President and Chairman, Tiffany & Co. in tribute to the land of its birth. While for Henry ‘Blue Zoisite’ echoed ‘blue suicide’, he was fascinated by this gemstone stating, “Tanzanite is the most important gemstone discovery in over 2,000 years”. In 1805, Abraham Gottlob Werner (1749 – 1817) described Zoisite, naming it after Sigmund Zois Freiherr von Edelstein (1747 – 1819), a Carniolan (present-day Slovenia) geologist, mineralogist, natural scientist, and nobleman. Other Zoisite gemstones include; Thulite, an opaque pink to reddish variety of Zoisite and Norway’s national gem; and Anyolite, derived from the Maasai word for ‘green’, this opaque apple-green Zoisite, black Amphibole, and Ruby combination is famously from Longido, also in Tanzania. Normally seen in gorgeous blues, bluish-purples and violets, Tanzanite’s different colors are due to varying amounts and ratios of chromium and vanadium. While Tanzanite’s’ best velvety blues can rival the finest Sapphires, it also comes in extremely rare and highly collectable fancy colors including, golden, green, lilac, orange, peacock (blue & green), pink, and yellow. Similar to Sapphires, these hues are collectively described as ‘Fancy Tanzanite’, with prefixes used to denote specific colors. While Tanzanite’s discovery has been officially attributed to Ndugu Jumanne M. Ngoma by the Tanzanian government, popular legend connects the find to nomadic Maasai herdsmen. Apparently, they spotted beautiful blue Tanzanite crystals that had been transformed from their original greyish-bronze by a grass fire. While this story alludes to how Tanzanite’s colors transform when heated, can a grass fire really reach the temperatures (370–650 °C) needed? This matter was recently put to rest by the highly-regarded gemologist and gemstone adventurer, Terry Coldham, BA (Geology), FGA, FGAA. Having never met anyone who had actually seen Tanzanite transform due to the heat of a grass fire, Terry decided to test the myth. After heating a selection of Tanzanite rough with a large quantity of dry grass, assisted by a light breeze, it was obvious that the gems had indeed turned blue. Manuel D’Souza staked the first Tanzanite claim, and legendary Scottish geologist Campbell Bridges, discoverer of Tsavorite, was the first person to bring Tanzanite to the GIA (Gemological Institute of America) for identification. The Maasai are a people forever linked to Tanzanite, and by sheer coincidence, they regard blue as a sacred spiritual color. Once bestowing blue beads and robes to women who had borne children, the Maasai have now adapted this tradition. Today, Maasai chiefs give Tanzanite to wives on the birth of a baby as a blessing for a healthy, positive, and successful life.
Rarity
On the Great North Road, between the plains of the Serengeti and the foothills of Mount Kilimanjaro, lies the trading town of Arusha, gateway to the famous gemstones of north‑eastern Tanzania. Part of East Africa’s Great Rift Valley, this area is one of the greatest gem deposits on Earth. Tanzanite was discovered in 1967 at a geologically unique, sole deposit, not far from Arusha in the arid Merelani foothills that rise from the hot Sanya plains. Five hundred and eighty‑five million years ago, conditions at the Mozambique Metamorphic Belt created Tanzanite in a way so rare that there is less than a one‑in‑a‑million chance of it occurring anywhere else.
Given that Tanzanite’s sole deposit scarcely covers 20 square kilometers, it’s no surprise the gem is routinely described in the jewelry-world as “a thousand times rarer than Diamonds”. In fact, Tanzanite ranks ninth on the top‑ten list of the world’s rarest and most valuable gems: Painite¹, Alexandrite², Taaffeite³, Jadeite⁴, Red Beryl⁵, Black Opal⁶, Grandidierite⁷, Benitoite⁸, Tanzanite⁹, and Poudretteite¹⁰. While the odd included Blue Zoisite crystal has been found in Pakistan, and some very limited Kenyan ‘Tanzanite’ (Zoisite) has occasionally been unearthed, Tanzania remains the world’s only commercial deposit, which has been segmented by the Tanzanian government into four blocks (A, B, C, and D).
Rapidly declining since the mid‑2010s, Tanzanite mining peaked in the late 20th century. In an August 2013 press release from the Tanzanite Foundation, a non‑profit organization dedicated to promoting Tanzanite, they stated, “At the current rate of mining, and given its single source and limited supply, it is estimated that there is less than 15 – 20 more years of Tanzanite left in the ground”. In a New York Times article dated 10th May, 2018, ‘Tanzanite, 50 Years Later’ by Melanie Abrams, she noted, “Experts disagree on how soon the world’s supply of Tanzanite will be exhausted, with some saying it is almost mined out”. With little activity in recent years, and the Tanzanian government cancelling or suspending numerous mining licenses in 2024–25 for dormancy and non‑compliance, this deposit’s decline has been further highlighted.
Tanzanite’s story is inseparable from its finite supply. While Tanzanite’s rare fancy colors have been occasionally found since its discovery, Peacock Tanzanite’s kaleidoscopic hues within a single crystal have only gained recognition since the early 2000s. These rare fancy colors are highly prized, yet they remain exceedingly scarce compared to the classic blue‑violets that define Tanzanite’s identity. This extremely limited supply is not only due to geological scarcity and increasingly constrained mining, but also the accelerating depletion of historic reserves. With most Tanzanite traded in 2026 now sourced from old‑vault mining, industry analysts project that this dwindling supply could be exhausted within two decades across all grades, with finer AAA and fancy colors disappearing far sooner.
Unlike its better‑known colors that are usually heated to improve their appearance, Peacock Tanzanite is one of the few gemstones that remain entirely natural and unenhanced, accentuating desirability, rarity, and value. If traditional Tanzanite is thought to be “a thousand times rarer than Diamonds”, how much rarer still is Peacock Tanzanite? This reality underscores Tanzanite’s position as a once‑in‑a‑lifetime gemstone. As Peacock Tanzanite and other fancy colors remain exceptionally scarce, their allure is magnified by the knowledge that each crystal represents a fragment of a vanishing gemological legacy.
Durability & Care
A popular jewelry gemstone well‑suited to everyday normal wear, Peacock Tanzanite (Mohs hardness 6.5 – 7) should always be stored carefully to avoid scuffs and scratches. Clean gently with mild soap and lukewarm water, carefully scrubbing behind the gem with a very soft toothbrush if needed. After cleaning, pat dry with a soft towel or chamois cloth.
Map Location
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