10 Rarest Blue Stones for Jewelry

#1 Rarest of Blue Stones: Garnet

Blue garnet is a rare and unusual variety of an already rare garnet, the color-change umbalite. What sets blue garnet apart is its remarkable color-changing property. The color of this gem ranges from blue to blue-green gray in daylight, and changes to pink or purple under incandescent light. This unique color-change property makes the blues of this garnet beautifully distinct.

Blue garnet obtains its peculiar coloration from the inclusion of high amounts of vanadium and smaller amounts of chromium. These elements interact with the crystal structure of garnet in a manner that causes its color to shift under a different lighting. Such a composition makes blue garnet extremely rare. Moreover, these gems typically occur in small quantities, making them even more scarce. As a result, finding high-quality blue garnet can be quite challenging.

Blue garnet came to light in the Bekily mine of Madagascar in the late 1990s, but the earliest find may have come as early as 1970. Other sources of blue garnet include Tanzania and Kenya.

#2 Rarest of Blue Stones: Diamond

Blue diamond is a natural diamond with a blue color, ranging in intensity from light to deep blue, often with a secondary hue, like violet, gray or green. The coloration of these blue stones comes from the presence of boron in the crystal.

Blue diamonds are among the rarest of all colored diamonds. Only one natural blue diamond comes into the market for every 100 Picasso paintings up at auction. The deeper the blue color, the rarer and more valuable the diamond is. This rarity ensues from the fact that boron, which causes the blue color in diamonds, is much less abundant on earth than elements like the yellow-causing nitrogen. Moreover, while present in higher quantities closer to the surface of the earth, boron is exceedingly rare in the earth’s mantle, where diamonds form – hence the rarity of the blue gem.

Still, humanity has known blue diamonds for centuries. These gems initially came from India, whence the French traveler Tavernier in the 1600s brought the most famous blue diamond: the Hope Diamond. Today, blue diamonds come from only a handful of mines. These include the Cullinan mine near Pretoria in South Africa and the Argyle mine in Australia. See —

#3 Rarest of Blue Stones: Musgravite

Blue musgravite is a rare and unusual gemstone that belongs to the beryl family. Discovered in 1967, musgravite first appeared in the Musgrave Ranges of Southern Australia, hence its name. Though better known in purple, musgravite sometimes occurs in blue, which ranges in shades from light sky blue to deeper blue tones.

Blue musgravite is one of the rarest gemstones in the world. The mineral musgravite by itself is extremely rare, even rarer than its parent stone taaffeite. From its discovery in 1967 to 2006, there were only 20 faceted musgravite gems identified. As a lesser-known variety of musgravite, the blue stones are even more scarce. Today, musgravite comes from a few locations, including Sri Lanka, Madagascar and Tanzania.

#4 Rarest of Blue Stones: Serendibite

Serendibite is an extremely rare silicate mineral first discovered in 1902. The stone came to light in Sri Lanka, whence it obtained its name — from the old Arabic name for the island, Serendib. Though best known in green and black, serendibite also occurs in blue, which can be pale or deep, and have undertones, such as green and violet.

Blue serendibite is one of the rarest gemstones in the world. Besides Sri Lanka, there is only one known source of serendibite, the neighboring country of Myanmar, and stones from the latter were typically black.

#5 Rarest of Blue Stones: Taaffeite

Taaffeite is an extremely rare silicate mineral first discovered in 1945 by Richard Taaffe, from whom the stone obtained its name. Due to similar physical appearance, taaffeite is often mistaken for spinel, and first came to light precisely in a collection of spinels. Though better known in mauve and purple, taaffeite also occurs in blue.

Blue taaffeite is exceptionally rare, with rather few specimens known to exist. Taaffeite by itself is a scarce mineral, and the blue variety is even rarer. Thus, finding a high-quality blue taaffeite is an exceedingly rare occurrence. Taaffeite comes from only a handful of locations, which include Sri Lanka and Tanzania.

#6 Rarest of Blue Stones: Benitoite

Benitoite is a rare and beautiful gemstone that is also the official state gem of California, USA. A mineral species composed of barium titanium silicate, benitoite is blue in color, ranging from a pale blue to deep blue. Benitoite may also be a bluish violet, but the most well-known color is a striking and vibrant blue. This blue color comes from the presence of trace amounts of titanium in the crystal.

Benitoite is one of the rarest of gems. Gem-quality crystals of benitoite are scarce, and large well-formed specimens are particularly uncommon. Initially mistaken for a sapphire due to its blue color, benitoite first came to light in 1907 in California’s San Benito County, whence the gem obtained its name. To this day, this region remains the primary source of benitoite, in recognition of whose rarity and beauty the state of California designated the stone as its official state gem.

#7 Rarest of Blue Stones: Grandidierite

Named after the French explorer Alfred Grandidier, grandidierite is a precious gemstone highly valued for its exceptional hues and rarity. Its color ranges from blue-green to greenish blue. Varying from light to deep shades, the captivating color of blue grandidierite can often resemble the mesmerizing blue of the ocean. This color comes from the presence of trace amounts of iron, and increases with the crystal’s iron content.

Grandidierite is extremely rare. Gem-quality specimens are even more scarce, and finding a grandidierite of a vivid blue hue is likewise unusual. Hence, it is challenging to find high-quality, well-cut blue grandidierite, making this gem highly sought after by collectors and enthusiasts.

Grandidierite first came to light in southern Madagascar in 1902. While there are reports of grandidierite coming from other sources – including Sri Lanka – Madagascar remains the most significant producer of this beautiful blue gem.

#8 Rarest of Blue Stones: Jeremejevite

Jeremejevite is a rare and precious gemstone known for its striking blue color. Though also found in colorless and yellow, the most popular color of jeremejevite is blue. This color can resemble the clear blue sky or the vibrant hues of the ocean, with the deep blue jeremejevite particularly prized. Jeremejevite is an aluminum borate mineral named after the Russian mineralogist Pavel Jeremejev, who discovered it.

Blue jeremejevite is extremely rare. High-quality, well-formed crystals are scarce. Thus, gem-quality specimens seldom come to light. The discovery of jeremejevite took place in 1883 in the Adun-Chilon Mountains of Siberia, Russia. The blue stones later appeared in several other locations, notable among which are Namibia and Myanmar. However, blue jeremejevite remains extremely scarce and challenging to obtain in significant quantities.

#9 Rarest of Blue Stones: Paraiba Tourmaline

Paraiba tourmaline is a unique type of tourmaline first discovered in 1989  in Brazil’s state of Paraiba, which gave the gemstone its name. This beautiful gem is famous for an intense neon blue to bluish green color. The vivid blue color often goes by the names ‘electric blue’ or ‘teal’. Copper is the primary element responsible for the electrifying blue and greenish-blue shades of paraiba tourmaline, and it is this coloring matter that distinguishes the paraiba from other varieties of tourmaline, including those of similar color.

Paraiba tourmaline is one of the rarest gemstones and accordingly the most valuable — often surpassing even the finest white diamonds in price per carat. The inclusion of copper, responsible for this blue gem’s remarkable color, is a rare occurrence in tourmaline crystals. Thus, high-quality specimens with intense, vivid colors are scarce. Moreover, with the depletion of deposits in Brazil, mining new paraiba tourmalines has become increasingly challenging.

Still, this precious variety of tourmaline came to light in a couple of other locations from across the world. Now, paraiba tourmalines also come from Mozambique and Nigeria, although the African stones come across as inferior and thus less valuable than the original Brazilian stones.

#10 Rarest: Tanzanite

Tanzanite is a variety of the mineral zoisite occurring in blue and violet. A relatively new gem, tanzanite came to light in 1967 in Tanzania, which gave the gemstone its name. The color of blue tanzanite often displays a hint of purple, and thus ranges in shades from blue to violet-blue, while also varying in intensity from pale to deep. The most valuable color is an intense, deep blue, followed by violetish blue. The striking blue color comes from the presence of trace amounts of vanadium within the crystal.

Tanzanite is extremely rare. Commercial production of the stone occurs in only one location, the Merelani Hills of Tanzania, thus making this stone significantly rarer than many other gems. The rare presence of vanadium in zoisite crystals limits the availability of tanzanite.

Honorable Mention: Spinel

Though best known in red, spinel also occurs in blue, varying in shades from light and pastel blues to deep and vivid hues. Popular for its cobalt-blue color, this variety of spinel can be reminiscent of the clear blue skies, or the serene waters of the ocean. The blue color comes from the presence of trace elements, particularly cobalt, and intensifies with the inclusion of iron.

Though not as rare as some other gemstones, blue spinels are relatively rare. Moreover, high-quality spinels of vibrant coloration are even rarer. The need for the inclusion of cobalt to produce its blue color makes this gem the rarest variety of the already rare spinel.

Spinel has a long history of use in jewelry, but the distinct identity of blue spinel as a variety of the mineral became more defined only with the advances of gemological knowledge. The blue variety occurs in a few locations, including Sri Lanka, Tanzania, Madagascar, Pakistan and Vietnam.

Rarest and Most Valuable

Due to their scarcity, the rarest of blue stones rank among the most valuable of gems. Their scarcity makes them highly sought after among collectors and gem enthusiasts, often resulting in premium prices when these gems become available for sale. Indeed, stones like benitoite, grandidierite and jeremejevite command incredibly high prices. Other remarkable qualities – such as the brilliance of diamond, the vivid color of paraiba tourmaline and the color-changing property of blue garnet – make these blue stones even more expensive.