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10 Rarest Gray Stones for Jewelry

Gray stones offer a unique and versatile option for jewelry and gemstone enthusiasts. Being of neutral color, grey stones can add an elegant and sophisticated touch to any piece of jewelry. These gray stones vary in rarity, ranging from the less common to the more abundant. Here are the ten rarest grey stones for jewelry.

Rarest of grey stones, benitoite
Rough benitoite crystal
From Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Rarest of Gray Stones: Benitoite

Benitoite is a rare gemstone first discovered in 1907 in San Benito County, California, USA, hence the name ‘benitoite.’ Though the primary color of benitoite is blue, variations in hue and tone can occur, resulting in shades that lean towards grayish tones. The gray color ensues from variations in chemical composition or the presence of impurities, such as crossite.

Due to its limited occurrence in nature, benitoite as a whole is a rare gem. This mineral occurs in only a few locations worldwide. The primary source of benitoite is the Benitoite Gem Mine of California, USA. Often opaque, the gray stones are typically not gem material. Hence, fine bluish gray benitoite is even rarer in comparison to the more commonly seen vibrant-blue variety.

One of the rarest of gray stones, diamond
Diamond
From Paul Gian, CC BY 3.0

2nd Rarest of Grey Stones: Diamond

There are natural diamonds that exhibit shades of gray. In recent years, gray diamonds have gained popularity. The grey stones display a range of hues from light to deep charcoal gray. This color results from the presence of hydrogen or the arrangement of carbon atoms within the crystal. These structural or chemical factors can influence the absorption and reflection of light, giving rise to the gray coloration.

Gray diamonds are rare in comparison to the colorless and some other fancy-colored diamonds, particularly the yellow and brown. Like other diamonds, the gray stones formed deep within the Earth’s mantle under intense heat and pressure, and came to light in various diamond mining regions. Countries like Russia, Australia, South Africa and Canada produce diamonds, including the gray variety. Yet the gray stones occur less commonly in nature. This makes them a sought-after choice for those seeking unique and distinctive diamond jewelry. See —

One of the rarest of grey stones, cat's eye chrysoberyl
Cat’s eye chrysoberyl

3rd Rarest of Gray Stones: Chrysoberyl

Chrysoberyl is a durable and relatively rare gemstone known for its exceptional brilliance and clarity. A variety of this gem occurs in gray of various shades, ranging from light to dark gray. Chrysoberyl in general is rare. While gray chrysoberyl may not be as well-known as other colors of the gem, this variety is generally less common than its more renowned counterparts, such as the greenish-yellow or yellow chrysoberyl. The gray chrysoberyl is rare on account of the scarcity of gray coloration in the mineral. The lower demand for the gray stones, moreover, leads to the scarcity of high-quality gray chrysoberyl in the market. Notable sources of chrysoberyl include countries such as Brazil, Sri Lanka, Madagascar, Tanzania and Russia.

 

Color-Change Chrysoberyl

An even rarer sort of gray chrysoberyl is the color-change variety, which often goes by the name ‘alexandrite.’ Alexandrite is a variety of the mineral chrysoberyl popular for its unique color-changing properties. Under certain lighting conditions, including incandescent light, this substance can exhibit shades of gray, ranging from light to dark gray. The gray color comes from the presence of certain trace elements, such as iron and titanium, which interact with light and affect its absorption and reflection, resulting in the gray coloration. Officially, however, predominantly gray stones go by the name ‘color-change chrysoberyl’ instead of ‘alexandrite.’

Due to its limited occurrence, color-change chrysoberyl is rare. Stones combining a gray coloration with the color-change phenomenon are uncommon too, and thus make great additions to gem collections. Notable sources of alexandrite include Brazil, Russia, Sri Lanka and Madagascar, but the presence of gray color-change chrysoberyl in these countries varies.

Gray Cat’s Eye

Another rare variety of gray chrysoberyl is the gray cat’s eye. Cat’s eye chrysoberyl is a variety of the stone that exhibits a chatoyancy effect, also known as ‘cat’s eye.’ The limited occurrence of chatoyant stones and the scarcity of high-quality specimens in the gem market keep the gray cat’s eye rare.

One of the rarest of gray stones, tanzanite
Tanzanite crystal showing different colors
From Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

4th Rarest of Grey Stones: Tanzanite

Zoisite is a mineral consisting of calcium aluminum silicate. This stone occurs in a range of colors, including gray, which ranges in shades from light to dark gray. The gray color comes from the presence of certain impurities, such as iron, which affect the way light interacts with the mineral, resulting in the gray coloration.

While zoisite, including the gray sort, is relatively common, a rare variety of zoisite also exhibits a gray color. This mineral is best known for its gemstone tanzanite, which first came to light in Tanzania in 1967 and has since gained popularity in the gemstone market. Tanzanite is a pleochroic gem, which means that the stone can display different colors when viewed from different angles. The colors most commonly associated with tanzanite are blue and violet-blue. However, gray can also appear in certain orientations. When viewed in specific directions — especially when the stone is less saturated or when light interacts with impurities — tanzanite can exhibit grayish tones. Thus, tanzanite can be gray as a result of its pleochroism.

Tanzanite, in general, is a rare gemstone. There is only one source of tanzanite in the whole world, which explains its rarity. This sole source of tanzanite is Tanzania, whence the stone obtained its name. The crystals occur specifically in the Merelani Hills near Mount Kilimanjaro.

One of the rarest of grey gems, star sapphire
From Daniel Torres, Jr.

5th Rarest of Gray Stones: Sapphire

Known for its hardness and beauty, sapphire is a precious gemstone from the mineral corundum, which also produces ruby. Whereas ruby occurs in red and sapphire is most popular in blue, the latter also occurs in a range of gray hues, from light gray to dark gray.

Gray sapphire is less common compared to the most popular blue variety. Both the scarcity of high-quality gray sapphire in nature and the consumers’ preference for other colors of sapphire result in the limited availability of the gray stones in the market. Yet there is a sort of gray sapphire that is even rarer and highly sought after.

Star sapphire is a unique variety of sapphire that exhibits a phenomenon known as asterism, in which a distinctive star-shaped pattern appears to move or shimmer across the surface of the gemstone when properly oriented.

Asterism ensues from the scattering of light by microscopic needle-like inclusions, such as rutile or hematite. These inclusions align in a specific pattern within the stone, creating the appearance of a star when light strikes the surface. Along with other colors, star sapphires occur in a range of gray hues, from light gray to dark gray. This color comes from the presence of certain trace elements or impurities within the crystal, such as iron or titanium.

Due to their unique optical phenomenon, gray star sapphires are rare. Their rarity, along with their beautiful optical properties, makes them desirable collector’s items and valuable gemstones. Star sapphires, including the gray variety, come from different locations where sapphires occur. Significant sources of sapphires include Sri Lanka, Madagascar, Myanmar, Thailand and Australia.

One of the rarest of gray gems, opal
Opal ring
From Danmekis, CC BY-SA 3.0

6th Rarest of Grey Stones: Opal

Opal is a type of gemstone known for its vibrant play of colors, which come in spectral hues that appear when light interacts with the stone’s internal structure. Opals consist of hydrated silica spheres arranged in a three-dimensional grid, which gives the stones their unique optical properties. Their body tone ranges from white through various shades of gray to black, and serves as the backdrop for the play of colors. The fire or iridescent flashes of colors – which can include blues, greens, purples and other hues – may thus shine against a gray background. The play of colors occurs through the diffraction of light as it interacts with the silica spheres and gaps within the gemstone.

Gray opal is less common compared to the white variety. While the former may not be as rare as some other types of opal, particularly the black variety, gem-quality gray opals with exceptional play of colors and desirable characteristics can still be relatively rare and valuable. Opals occur in various locations – including Australia, Ethiopia, Mexico and the United States – but the Australian gray opals, particularly those from New South Wales and South Australia, are highly popular for their quality and play of colors.

One of the rarest of grey stones, pearls
Tahitian pearls
From Olivier Dugornay, CC BY 4.0

7th Rarest of Gray Stones: Pearl

Pearls are organic gemstones formed within the soft tissue of certain mollusks, particularly oysters. Gray pearls are known for their unique coloration and iridescent beauty. The greys stones exhibit a range of hues, ranging from light gray to dark charcoal gray. The color comes from the concentration of pigments, such as melanin, present in the mollusk’s soft tissue and contributing to the gray coloration.

Gray pearls occur in various regions around the world where pearl-producing mollusks live. Freshwater mollusks, such as those in the rivers and lakes of China, yield the grey stones, which are significantly more common than their saltwater counterparts. Yet the most important sources of deep-colored gray pearls are the countries producing the saltwater variety, which go by the name ‘Tahitian pearl.’

Tahitian Pearl

Tahitian pearls are a type of cultured pearl that originates from the black-lipped oyster, better known as the Pinctada margaritifera. This species inhabits the waters of French Polynesia, particularly around the islands of Tahiti. While Tahitian pearls are commonly known as ‘black pearls,’ they in fact occur in various shades of gray, including silver gray, charcoal gray and tones of gray with hints of green, blue or purple. Their distinctive color, combined with their natural beauty and scarcity, contributes to their desirability.

Gray Tahitian pearls are rare and highly sought after in the pearl market. High-quality gray Tahitian pearls with desirable characteristics and intense gray coloration are even rarer. The rarity of gray pearls is due to the limited geographic range of the black-lipped oyster, as well as the relatively low production of the grey stones. Besides French Polynesia, other sources of gray pearls include the Cook Islands, Fiji and Marshall Islands.

These regions are known for their pearl farms and the cultivation of the black-lipped oysters that produce the Tahitian pearls. Pearls in general are highly prized gemstones, and jewelry enthusiasts seek the grey stones on account of their peculiar appeal.

One of the rarest of gray stones, spinel
Rough spinel
From S kitahashi, CC BY-SA 3.0

8th Rarest of Grey Stones: Spinel

Composed of magnesium aluminum oxide, spinel is a gemstone prized for its hardness, brilliance and colors, one of which is gray. Spinel can display various shades of gray, ranging from light to medium and dark gray. The gray color comes from the presence of certain trace elements, particularly iron, which affect the way light interacts with the gemstone, resulting in the gray coloration.

Gray spinel is less rare compared to some other spinel colors, such as red or blue. Still, high-quality gray spinels of perfectly neutral gray color remain relatively rare. Gray spinel occurs in several countries around the world, with significant supply coming from Sri Lanka, Myanmar, Thailand and Cambodia.

One of the rarest of grey gems, zircon
Zircon ring
From Billjones94, CC BY-SA 4.0

9th Rarest of Gray Stones: Zircon

Known for its brilliance and fire, zircon is a naturally occurring gemstone composed of zirconium silicate. Among its wide range of colors are different shades of gray, ranging from light gray to medium and dark gray. The gray color in zircon comes from the presence of certain impurities, particularly iron oxide, which affect the absorption and reflection of light, resulting in the gray coloration.

Gray zircon is not as rare as some other colors of zircon, such as the natural blue stones. However, the availability of gray stones with excellent clarity, color and cut can still make them relatively rare. Notable sources of gray zircon include Sri Lanka, Thailand, Australia, Cambodia and Tanzania.

One of the rarest of gray gems, moonstone
Moonstone
From James St. John, CC BY 2.0

10th Rarest of Grey Stones: Moonstone

Moonstone is a variety of the mineral feldspar known for its unique play of adularescence, which is a shimmering effect that appears to move across the stone. Though most popular as a pearly or milky gem, moonstone also occurs as gray stones, ranging in tone from light gray to deeper shades. The translucent whitish-gray stones showing iridescence are especially representative of the gem. The specific shades can vary depending on the presence of inclusions within the stone, while the characteristic glow or shimmer comes from the scattering of light by thin, alternating layers of orthoclase and albite within the crystal. This scattering of light gives rise to the peculiar pearly sheen often seen in moonstone, including the gray variety.

Gray moonstone is not extremely rare, but may be less common compared to other varieties of moonstone, such as the classic white or peach-colored gems. While moonstone itself is relatively common, finding high-quality moonstone with a desirable gray color and strong adularescence can be more challenging. Moonstone occurs in several locations worldwide, including Sri Lanka, India, Myanmar, Australia and Madagascar.

Rarest, But Not the Most Sought-after

Gray stones can be rare, but demand for them may not be as high compared to gemstones in more vibrant colors. Hence, despite their rarity, grey stones may not command the same level of market values as gemstones in more popular colors. Still, there are individuals who appreciate the unique charm and understated elegance of gray stones. Ultimately, the rarity and desirability of grey stones can vary depending on individual taste, fashion trends and cultural preferences.

Article published

Going for Diamond

The author wrote this article in the course of his research for an upcoming book. In doing so, he discovered that gray is rather rare compared to other colors of the gem, and is getting increasingly popular. The writer’s book, ‘Diamond, Its Magic and History,’ is currently in progress. In the meantime, you can check out the author’s other work —

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