Triphylite Gemstone: Properties, Meanings, Value & More

Triphylite (also spelled tryphylite or triphyllite) is a commonly grayish-blue or grayish-green mineral closely related to lithiophilite.

Is triphylite rare? As a mineral, no — triphylite minerals are actually among the most common accessory phosphate minerals in granite pegmatites. But triphylite gemstones are very rare, and demand for them fluctuates.

One rare type of triphylite is color-changing, displaying different colors under different types of lighting.

Eager to know more? Join us as we go over all of triphylite’s uses, prices, characteristics, history, and more!

Pictured above: Slightly green triphylite crystal with sharp faces; Rice Northwest Museum Collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

What Is Triphylite?

Triphylite is a very rare semi-precious gemstone found in grayish shades of blue or green usually, though oxidation can make many specimens appear black.

Astrologically, triphylite is recommended as a Libra birthstone.

Outside of gems and mineral collections, what is triphylite used for?

Triphylite Uses

Natural and synthetic triphylite have been researched as materials — specifically electrodes and cathodes — for lithium ion batteries.

Lithium ion (or Li-ion) batteries are rechargeable batteries that store energy by using the properties of lithium ions, making them sources of renewable, cleaner energy as they can be reused hundreds of times.

In fact, the 2019 Nobel Prize in Chemistry was awarded to John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino for developing these batteries because they created so many options for wireless, fossil-free energy.

Pictured above: Massive or vein-filling triphylite specimen with small dark crystals on surface, probably vivianite; Academy of Natural Sciences Philadelphia Collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Triphylite Specifications & Characteristics

A lithium iron phosphate mineral, the formula for triphylite is LiFe2+(PO4). Some write the formula as Li(Fe+2, Mn+2)PO4 + Mg to account for the common impurities manganese and magnesium. Calcium is also a common impurity.

Manganese is often present in triphylite because it forms a series with the lithium manganese phosphate lithiophilite. Some triphylite specimens are intermediate, with varying iron to manganese ratios. Magnesium impurities can also substitute for iron or manganese.

The term “lithio-ferro-triphylite” was proposed in 1915 for the triphylite end member in the series.

The mineral is also in the eponymous triphylite group of anhydrous (waterless) phosphates, alongside:

• Heterosite

• Purpurite

• Sicklerite

• Lithiophilite

• Natrophilite

• Ferrisicklerite

• Karenwebberite

• Simferite

What is the Crystal Structure of Triphylite?

Triphylite minerals have a similar structure to olivine-type minerals. The stone’s atomic grouping matches that of monticellite and olivine.

Triphylite falls under the orthorhombic crystal system. The crystals have prismatic and stout structures, typically with rounded crystal faces or coarse, uneven surfaces.

However, triphylite rarely forms as crystals. Usually, the mineral occurs as cleavable or compact masses. Sometimes triphylite is granular or found in clumps intergrown with other crystals.

Triphylite Properties Listed:

Note: Some of triphylite’s properties can change based on oxidation, the specimen’s place in the triphylite-lithiophilite series, and the presence of manganese or magnesium.

• Mohs hardness: 4-5

• Color: Usually greenish-gray, grayish-green, bluish-gray, or grayish-blue; Can be brownish-green or clove brown (medium-dark orange); Oxidized areas - brown to black;

• Crystal structure: Orthorhombic

• Luster: Vitreous, sub-vitreous, resinous, or sub-resinous

• Transparency: Translucent to transparent

• Refractive index: 1.685-1.720; Increases with oxidation (1.790-1.820) and/or higher iron content; Can decrease with higher manganese content or magnesium substituting for iron

• Density: 3.42-3.59; Increases with higher iron content, decreases with higher manganese content

• Cleavage: Perfect on {001}, Distinct/Good on {010}, Indistinct/Poor on {011}; Brazilian material - Perfect on {001},

• Fracture: Subconchoidal or uneven/irregular

• Streak: Colorless/white or grayish-white

• Luminescence: None

• Pleochroism: Rarely present - orange or orange-brown to green or grayish-green

• Birefringence: 0.004-0.008; Oxidized specimens - 0.030; Brazilian material - 0.011-0.015

• Dispersion: Strong

• Optical effects: Sometimes color-changing (Brazilian material)

Pictured above: Blue-gray triphylite crystals in quartz vug with muscovite; John Sinkankas Collection with his accompanying card | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Triphylite History

The name “triphylite” derives from the Greek terms tri, meaning “three” or “threefold,” and phylon, meaning “family.” This name reflects the three cations in triphylite’s formula: lithium (Li+), ferrous iron (Fe2+), and manganese (Mn2+).

German chemist and mineralogist Johann Nepomuk von Fuchs chose the name when he wrote the first description of triphylite in 1834. The description was based on specimens from the Hennenkobel Mine (Hühnerkobel Mine in German) in Bavaria, Germany.

In his description, Fuchs notes that the mineral at first resembled triplite — a manganese, iron, magnesium, and calcium phosphate described in 1813 — in many ways, but his analysis proved triphylite was a different mineral.

The first synthetic triphylite (with the formula LiFePO4) was created and studied by Russian crystal chemists Olga V. Yakubovich, Mikhail A. Simonov, and Nikolay Vasilyevich Belov in 1977.

Brazilian Triphylite Discovery

In 2008, gemologist and owner of The Gem Trader Brad Payne brought attention to a new source of facetable triphylite material: Galiléia, Minas Gerais, Brazil.

Not only were there around 200 carats of faceted triphylites from this locality, but some of the specimens had unique traits like color-changing properties, strong pleochroism, and larger sizes.

Triphylite Healing Properties

As a popularly blue healing stone, triphylite’s metaphysical properties match those of other blue gemstones, encouraging serenity and reflection.

The crystal can be used as a throat chakra stone.

Physical Healing

Physically, triphylite is said to treat issues related to:

• Sexual health

• Reproductive health

• Low energy

• Weak muscles or bones

Emotional Healing

Crystal healers recommend triphylite if you’re looking for more balance, grounding, and inner peace. It’s believed to help you let go of self-doubt, soothe the soul, and attract positive energies while dispelling negativity.

Pictured above: Sharp, dark green triphylite crystal from New Hampshire, USA | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Triphylite Gemstone Properties

Besides rarity, triphylite value also depends on color, cut, clarity, transparency, and carat weight.

Color

Triphylite is generally blue or green with gray undertones. Portions that are oxidized are brown to black. You may see yellowish-brown, honey yellow, salmon, clove brown, or orange triphylite if the specimen is closer to lithiophilite in the series.

Vivianite inclusions may cause blue hues in triphylite.

Most valuable are color-changing triphylite gems. In daylight to incandescent light, these can shift from:

• Greenish-brown to brownish-pink or purple

• Green to brownish copper red

• Reddish-brown to greenish-brown or olive green

• Reddish-brown to deep red

Color-changing specimens, only currently known from Brazil, also display strong orange or brown to green or greenish-gray pleochroism (different colors at different viewing angles).

More vibrant, unaltered triphylites are more valuable.

Cut

Given the rarity of facetable material and the mineral’s perfect cleavage (which makes cutting difficult), faceted triphylites are rare, raising their value. Most are faceted into emerald or triangular step cuts.

Most gem-quality triphylite rough is cut into cabochons. Even more common are quartz cabochons with triphylite inclusions.

Clarity & Transparency

Clarity describes the degree of visible inclusions in a gem, which can lower its transparency and value.

Potential inclusions in triphylite include:

• Needles

• Fingerprints

• Lamellar, platy sarcopside

• Crystals

• Hydrous phosphate minerals

• Liquid inclusions

Triphylite has also been found as an inclusion in other stones like fluorapatite and quartz. Notably, some quartz from Brazil has been found with color-changing triphylite inclusions!

Carat Weight & Size

Large triphylite crystals have been found in South Dakota, USA — up to 6 feet long! — but they’re often not attractive due to lower transparency and oxidation.

Brazilian triphylite rough has yielded small faceted gems mostly up to 2 carats, but sometimes over 9 carats.

Pictured above: Patch of brown radiating frondelite crystals with dark triphylite cleavages; From Brazil; JSS specimen and photo | Image credit: John Sobolewski (JSS)

Triphylite Formation & Sources

Triphylite minerals form in lithium-bearing, complex zoned granite pegmatites. It’s a primary mineral and often alters into secondary phosphate minerals.

Alteration products of triphylite include phosphosiderite, heterosite, and phosphophyllite.

Minerals commonly associated with triphylite include:

• Alluaudite

• Ferrisicklerite

• Graftonite

• Heterosite

• Hureaulite

• Muscovite

• Quartz

• Rockbridgeite

• Vivianite

Geographically, where is triphylite found?

Mining Locations

The best source for facetable triphylite is Brazil. The largest known crystals have come from South Dakota, USA, but New Hampshire is another source for large, high-quality triphylite crystals.

Additional sources for triphylite gemstone material are:

• Finland

• France

• Germany

• Sweden

• USA (California, Maine, Massachusetts)

Other notable sources for triphylite specimens are the Czech Republic, Canada, and Arizona (USA).

Pictured above: Triphylite specimen with special cleavage feature | Image credit: Pacific Museum of Earth from Canada, CC-BY-SA-2.0

Triphylite Price & Value

Demand for triphylite fluctuates, so prices can change. Sometimes, faceted triphylite gems are $250 per carat; other times, they’re $4,500 per carat.

Currently, in November 2023, faceted triphylite gemstones cost around $40 to $100 per carat. Faceted color-changing triphylite gems cost around $400 to $570 per carat.

Quartz cabochons with triphylite inclusions are roughly $15 to $45 per carat.

Rough triphylite specimens range from about $10 up to $1,250. The most expensive specimens are large with other rare minerals like landesite or vivianite. Some may be antiques.

Blue triphylite crystals on a matrix generally go for $20 to $75 each.

Triphylite Care and Maintenance

First, note that triphylite has been considered a medium risk mineral in terms of toxicity due to its lithium content. However, you’re unlikely to suffer toxic side effects from triphylite. Just be sure to wear safety equipment if cutting triphylite and don’t put it in your mouth.

For gemstone care, we recommend getting protective settings on triphylite jewelry, given its softness and perfect cleavage.

Keep it away from hydrochloric or sulfuric acid. Clean triphylite with warm water, mild soap, and a soft microfiber cloth.

Want to Try a Triphylite for Yourself?

Triphylite is a fascinating stone with not only potential for making cleaner energy but also bringing you positivity. Its grayish-blue to green hues are reminiscent of ocean mornings, paralleling its soothing energies.

Buy triphylite and other terrific gemstones today!