Boleite Gemstone: Properties, Meanings, Value & More

Boleite (pronounced BOH-lee-eyet) is a gemstone not widely known to the public but known among collectors of rare minerals and gems for the stone’s stunning coloring.

Boleite is a stunning deep blue, ranging from indigo to Prussian blue. Besides its colors, collectors also seek out boleite for its peculiar composition ( with large amounts of multiple metals) and intriguing pseudocubic twinning.

Boleite is very rarely found crystallized, only growing up to 2cm most times. Cut boleite gems are even rarer, and transparent, faceted boleites are incredibly rare.

Want to know more? Read on to learn all about boleite’s characteristics as a mineral and gemstone, along with its history, healing properties, and prices.

Pictured above: Single thumbnail boleite crystal with typical cubic shape and iridescent azure blue color | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

About Boleite Stone

Boleite is a very rare semi-precious gemstone almost exclusively known among collectors. It’s also been called “argentopercylite,” meaning silver-bearing percylite. Percylite is a mixture of boleite and pseudoboleite.

Astrologically, boleite can benefit any of the water signs — Cancer, Scorpio, or Pisces.

As far as boleite’s uses go, it was first discovered in a copper mine and served as a very minor silver, copper, and lead ore. However, it’s too rare to be an ore today.

Boleite Specifications & Characteristics

In a general sense, boleite is a complex halide mineral. Halides are compounds created through a reaction of a halogen acid (like hydrochloric acid) with a base. Other halide minerals include halite and fluorite.

More specifically, however, boleite is a potassium lead silver copper hydroxychloride. The boleite formula currently approved by the International Mineralogical Association (IMA) is KAg9Pb26Cu24Cl62(OH)48.

Earlier versions of the formula didn’t include potassium and did include water, like the formula Pb26Ag9Cu24Cl62(OH)47·H2O.

In terms of boleite’s crystal habit, the stone usually forms cube-shaped crystals, sometimes with modified faces. Some display pseudocubic penetration twinning along three perpendicular, interpenetrated angles. Many boleite specimens are found as tiny crystals on a matrix of their host rock or another mineral like anglesite.

The stone’s crystal system isn’t entirely agreed upon. Some classify it as isometric (cubic), while others classify it as tetragonal and only pseudo-cubic.

Minerals related to boleite, with the same bright blue cubic form and complex crystal structure, include pseudoboleite, cumengite, and diaboleite.

Boleite’s properties listed:

• Mohs hardness: 3-3.5

• Color: Indigo, Prussian blue, or blackish-blue

• Crystal structure: Isometric/cubic; Sometimes classified as tetragonal

• Luster: Vitreous or pearly

• Transparency: Translucent to opaque

• Refractive index: 2.03-2.05

• Density: 5.05

• Cleavage: Perfect on [001], good on [101]

• Fracture: Uneven/irregular

• Streak: Greenish-blue

• Luminescence: None

• Pleochroism: None

• Birefringence: None

• Dispersion: None

Moving away from mineralogy, what is the spiritual meaning of boleite?

Pictured above: Classic, old-time collection of five lustrous, indigo-blue boleite cubes from the Amelia Mine at Boleo, Mexico; Richard Hauck Collection; Collected during active mining in late 1800s; Boxed set comes with label from the late, well-known worldwide dealer Dr. A.E. Foote | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Boleite Meaning & History

Like the blue of still ocean waters and skies, blue gemstones like boleite represent tranquility and harmony. Boleite’s metaphysical properties can also encompass camaraderie, good fortune, and balance.

History

Boleite is named for its discovery at the El Boleo mine near Santa Rosalia, Baja California, Mexico.

It was first described — erroneously as an oxychloride mineral — by French crystallographer François Ernest Mallard and Boleo mining engineer Bernard Louis Philippe Édouard Cumenge in 1891. Mallard would also publish a description of boleite with cumengeite and percylite found at the mine.

The El Boleo mine was likely discovered by rancher José Rosas Villavicencio in 1868, and small-scale copper ore mining continued until 1885. Commercial-scale mining began in 1885, operated by French company Compagnie du Boleo.

By the turn of the century, El Boleo was hailed as Mexico’s copper capital, producing roughly half of the country’s total copper at around 11,000 tons annually. This prosperity continued until the French company’s prior tax exemption expired and they shut down the mine in 1954.

From there, ownership and operation of the mine switched to the Mexican government mining bureau until 1984, then to a Canadian company from 1992 to 2012, and finally to a Korean company who still operates it.

Boleite Gemstone Healing Properties

Though rare, boleite crystals are still used as healing stones for various physical, emotional, and spiritual issues.

Physical Healing

Physically, boleite is said to treat issues related to:

• Headaches

• Throat pain

• Thyroid

Emotional Healing

Emotionally, some purported boleite gemstone benefits include soothing heightened emotions like anger or stress, calming anxiety, and boosting confidence.

Chakra Healing

Chakra healing involves balancing energy flow by opening blocked energy centers (chakras). Boleite is a chakra stone for the throat and third eye chakras.

The throat and third eye chakras deal with communication, intuition, and perception. Once opened, you’ll be able to understand and express your true self and understand hidden spiritual insights of the world.

Pictured above: Group of 97 indigo-blue boleite cubes from personal collection of Ed Swoboda, all with good color and mostly complete | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Boleite Gemstone Properties

Boleite gemstone value isn’t graded like other gems, given its extreme rarity. But we’ll still go over how the standard grading factors apply to boleite:

• Color: Boleite ranges from indigo to Prussian blue to blackish-blue. More saturated blue colors will carry higher value. It may appear blue-green in transmitted light.

• Cut: Given boleite’s softness and rarity, specimens are only cut for collectors. Any faceted boleites would be extremely rare.

• Transparency: Boleite’s range of tones can make it appear translucent to opaque. Crystals with greater translucence, closer to transparent, will be more valuable.

• Size: A few boleite crystals have been faceted into small stones, but these aren’t usually available on the market. Most rough boleite crystals are small, so larger, attractive specimens may carry higher value.

There are no known treated or synthetic boleites for sale.

Before it goes to the market, how is boleite formed?

Pictured above: Razor-sharp boleite crystal perched in matrix; From the Laithauser Collection, obtained after big find by Larson and Swoboda in 1979 | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Boleite Formation & Sources

Boleite forms in copper and lead deposits as a secondary mineral. Secondary minerals form when the rock or area around them undergoes changes like weathering, oxidation, or metamorphism, transforming the former (primary) minerals present into new (secondary) minerals.

In boleite’s case, sulfide minerals in copper and lead deposits react with solutions containing chloride. The resulting secondary minerals are boleite and similar minerals like cumengite.

However, boleite can also be found in smelter slags put into the ocean where they’re “leached” by the ocean water.

Smelter slags are certain by-product compounds (slags) removed when an ore is heated to extract a base metal (smelting). This is a type of pyrometamorphism, where some secondary minerals are altered through the process of smelting or when slag is altered.

The minerals pseudoboleite and cumengeite are commonly found epitaxially with boleite, deposited in thin crystal layers on top of boleite.

Minerals found associated with boleite include:

• Anglesite

• Atacamite

• Bideauxite

• Caledonite

• Cerussite

• Cumengeite

• Gypsum

• Leadhillite

• Matlockite

• Paralaurionite

• Paratacamite

• Phosgenite

• Pseudoboleite

Geographically, where is boleite found?

Mining Locations

The only currently known source of sizable, well-formed or epitaxially overgrown boleite crystals is the Amelia Mine in Baja California, Mexico.

Other sources of boleite include:

• Arizona, USA

• Australia

• England

• Chile

• Greece

Diabolite, discovered in England in 1923, has been found in:

• Australia

• Austria

• Chile

• France

• Germany

• Greece

• Iran

• Italy

• Russia

• South Africa

• UK

• USA

Next, we’ll let you know what to expect for boleite gemstone prices.

Pictured above: Cumengeite and pseudoboleite on boleite - example of epitaxial growth where pseudoboleite overgrow the boleite cube; Dick Jones collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Boleite Price & Value

Boleite stones available for sale are almost always rough crystals and specimens.

The priciest specimens have well-formed, large, and attractive boleite crystals on a matrix with other rare minerals like penfieldite. These go for around $400 to over $3,000.

Small boleite cube crystals range from $40 to $280. Twinned boleite crystals go for about $30 to $280, some reaching $700.

Boleite formed with or on anglesite ranges from around $100 to $300, the highest reaching $950.

Jewelry is rare, but boleite pendants are about $150.

Boleite Care and Maintenance

It’s important to note that boleite has a high toxicity risk due to it containing the copper and lead. It’s also soft, meaning fibers will scratch off easily, and soluble in acids. It’s best to store boleite in a display case away from any children or pets, and wear safety gear when handling it.

In terms of gemstone care, boleite is inert in water but soluble in acids. We recommend keeping it enclosed to avoid dust and not washing it.

Pictured above: Mixed sizes of boleite thumbnails in complete suite of boleite's different crystal habits; Found by field collectors Bill Larson and Ed Swoboda in 1973; Originally from Dr. Miguel Romero collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Boleite: A Rare but Beloved Blue Collector’s Stone!

From stunning deep blue colors to unique cubic or twinned shapes to an unusual composition, boleite is a treat for collectors. Add its rarity on top and you have a gorgeous gem suited for any collection!

Buy boleite and other unique gemstones today!