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Herderite Gemstone: Properties, Meanings, Value & More

ヘルデライトの宝石：特性、意味、価値など

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Herderite is a lesser-known gemstone beloved by some collectors for its intriguing twinning patterns like “fishtail” or cyclic shapes.

What color is herderite? It’s found in various colors, including colorless, green, blue-green yellow, pink, gray, purple, or some combination of these.

Is herderite rare? Yep, herderite minerals are rare and gem-quality, facetable crystals are even rarer, especially in large sizes.

Despite its lack of popularity and abundance, herderite still makes a gorgeous gemstone with plenty of benefits. Come along as we break down herderite’s properties, prices, healing powers, and history.

Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

What Is Herderite?

Herderite is a rare semi-precious gemstone that may also be called:

• Allogonite

• Glucinite

• Fluor-herderite

The stone can be a substitute for birthstones like citrine (for November) or tourmaline (for October). Individually, herderite is a zodiac stone for fiery Aries signs.

The stone is rarely found in pure form, which takes us to its composition and other mineral properties.

Herderite Specifications & Characteristics

The mineral herderite is composed of calcium, beryllium, and phosphate. The herderite formula may be written as CaBe(PO4)F or CaBe(PO4)(F,OH) to account for the common impurity hydroxide. Hydrogen is another common impurity. Other possible impurities include traces of iron, manganese, lead, or yttrium.

Herderite is in the herderite group of the gadolinite subgroup. The herderite group is separated into drugmanite and herderite subgroups, the latter of which includes herderite, bergslagite, and hydroxylherderite.

Hydroxylherderite and herderite form a series, with herderite at the fluorine-dominant end and hydroxylherderite at the hydroxide-dominant end. Since hydroxylherderite is actually more common than herderite, many hydroxylherderite stones are mislabeled as herderite. (More on the differences between them in the next section).

The crystal habits of herderite include prismatic tabular crystals and fibrous aggregates that can be botryoidal (grape-like clusters) to spheroidal. Crystals can also be pseudo-orthorhombic or pseudo-hexagonal.

Twinning is quite common in herderite, particularly fishtail contact twinning. Fishtail twins are two crystals joined on the side and mirroring each other, creating a fishtail- or chevron-like pattern.

Herderite properties listed:

• Mohs hardness: 5-5.5

• Color: Colorless, gray, yellow, green, yellow-green, greenish-yellow, pink, violet, reddish-purple

• Crystal structure: Monoclinic

• Luster: Vitreous or sub-vitreous

• Transparency: Transparent to translucent

• Refractive index: 1.556-1.627

• Density: 2.95-3.02

• Cleavage: Indistinct/poor on {110}, interrupted

• Fracture: Conchoidal or subconchoidal

• Streak: White

• Luminescence: Fluorescence often present - Pale green, violet, pale yellow, deep blue, or green in LW-UV & pale yellow, blue, violet, or green in SW-UV; X-ray colors, often with persistent phosphorescence - orange or pinkish-orange; Cathodoluminescence possible

• Pleochroism: Sometimes present, usually weak - usually yellow to yellow-green or yellowish-green to green, possibly yellow to pink, gray to violet, or green to brownish-green

• Birefringence: 0.023-0.033

• Dispersion: 0.017 (moderate)

Pictured above: Hydroxylherderite | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Herderite vs Hydroxylherderite

As mentioned above, herderite and hydroxylherderite are the fluorine- and hydroxyl-dominant end members of their series, respectively. The ratio of fluorine to hydroxyl is what distinguishes them.

Unfortunately, their compositions are difficult to distinguish because fluorine, oxygen, and hydrogen can’t be detected with the traditional technique of Energy Dispersive X-ray Fluorescence (EDXRF) spectrometry.

However, there are some slight differences in their mineral properties that can help you estimate which one is which:

Optic Sign: Generally, hydroxylherderites will have a biaxial (+) optic sign and herderites will have a negative sign (though some herderites have a positive sign).

Refractive Indices: Higher fluorine content means lower refractive indices, so herderites generally have lower RI ranges than hydroxylherderites.

Stepping away from mineralogy, what is the spiritual meaning of herderite?

Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Herderite Meaning & History

The herderite crystal symbolizes transformation, renewal, and new beginnings.

Herderite’s metaphysical meaning is often tied to the mind, as it’s believed to create new neural pathways, stimulate your brain, and help you access mental strengths you’re not harnessing — be it psychic powers or simply creativity.

History

Where did herderite come from? The first official discovery of herderite was in the Sauberg Mine of Saxony, Germany, in 1828. Early on, mineralogists thought herderite may be related to apatite, partly for its resemblance to the yellow-green to green apatite gems called “asparagus stone.”

Austrian mineralogist Wilhelm von Haidinger published the first description, naming herderite after Sigmund August Wolfgang von Herder, the Saxon mining director.

German mineralogist August Breithaupt also used the name “allogonite” for the stone in 1830 and 1832. This derived from the Greek terms άλλος and γωνία, meaning “another angle,” in reference to its angles differing from that of apatite.

Yet another name was “gluconite,” used by American geologist William Earl Hidden in 1884 in reference to the stone’s composition as a “glucinum calcium phosphate and fluoride.”

Both “gluconite” and “allogonite” have become obsolete synonyms, however.

Other herderite mines outside of Germany popped up over time, but the most important ones were in Brazil, discovered in the 1970s. Since then, Brazil has become the top source for herderite gemstone material.

Back to the spiritual side, what are the benefits of the herderite stone?

Herderite Healing Properties

As a commonly green healing stone, herderite has the rejuvenating and harmonizing properties inherent to green gemstones. It’s also a great solar plexus or heart chakra stone.

Physical Healing

Physically, herderite crystal benefits are said to include treating problems related to:

• Brain function

• Head injury

• Migraines

• Fatigue

Emotional Healing

Emotionally, herderite is believed to help you change your perspective, be it to channel your true power with confidence, make wise decisions in emotionally charged situations, or move on from a particularly painful period.

Pictured above: Deep purple hydroxylherderite crystal | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Herderite Gemstone Properties

Besides rarity, other factors affecting herderite gemstone value are color, cut, clarity, and carat weight. The stone has no known synthetic versions or treatments.

Color

Most herderite gemstones are colorless or yellow to green. Yellow to green colors likely come from manganese impurities. Rarer specimens are pink to violet, which can be more valuable.

Since not all herderite stones have pleochroism, this feature can be another value boost.

Cut

Herderite specimens that have the quality and size for faceting are rare; many faceted stones are hydroxylherderite. Common faceted cuts include pear, emerald, cushion, round, and radiant shapes.

The stone may also be cut into beads, tumbled, or sold uncut (rough).

Clarity

Many high-quality faceted herderite gems have no visible inclusions, but inclusions are possible. Possible inclusions include:

• Partially healed fractures (sometimes containing fluid)

• Small feathers

• Scattered “pinpoint” inclusions

• Needle-like inclusions (isolated or in small clusters)

• Two-phase inclusions

• Growth tubes

Additionally, herderite’s strong birefringence can cause strong doubling of the facets, meaning it may look like there are twice as many facets as there actually are.

Carat Weight

Herderite material from most sources is scarcely large or gem-quality, but Brazil has produced some large, well-colored, gem-quality crystals (up to about fist size).

A few herderite gems have been 25 to 40 carats, with one of the largest faceted herderites being over 161 carats!

Material from Maine, USA, is usually pale or colorless and yields 1- to 5-carat faceted gems.

Herderite Formation & Sources

Herderite usually forms during hydrothermal deposition, meaning hot water carrying dissolved elements gets into rock crevices and gradually evaporates, leaving the elements to crystallize.

Most herderites are found in pegmatites, often near apatite minerals.

Other minerals associated with herderite include:

• Tourmaline

• Quartz

• Albite

• Beryl

• Elbaite

• Muscovite

• Foitite

• Cleavelandite

• Feldspars

Mining Locations

Where is herderite found? Today, Brazil is the top source for herderite gem material, though Pakistan is another top contender. Both sources produce hydroxylherderites, which also may come from:

• Austria

• Germany

• Russia

• USA (Maine, New Hampshire)

Other possible herderite sources:

• Argentina

• China

• Czechia

• Finland

• Italy

• Myanmar

• Namibia

• Spain

• Sweden

• UK

It’s important to note that many gems labeled “herderite” are actually hydroxylherderite. Technically, specimens confirmed to be herderite through analysis have only been identified in Myanmar, Brazil, China, and Namibia.

Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Herderite Price & Value

Faceted herderite gemstones are generally the priciest, given their rarity, but prices vary according to color, size, and quality.

The general herderite price per carat ranges by color are:

• Light Green: $100 to $350 per carat

• Medium to Dark Green: $70 to $200 per carat

• Purple: $50 to $170 per carat

• Yellow: $40 to $160 per carat

• Colorless: Around $90 per carat

Rough herderite ranges from around $10 for small crystals to nearly $1,300 large, museum-quality specimens.

Herderite Care and Maintenance

Before we wrap up, let’s discuss gemstone care.

Herderite jewelry will be somewhat fragile, given herderite mid-range hardness, so we recommend only occasional wear. Rings should definitely have protective settings.

Avoid mechanical cleaning systems (e.g. steam or ultrasonic). The best cleaning method is with a soft toothbrush, mild soap, and warm water.

Store separately from other gemstones to avoid scratches.

Pictured above: Green hydroxylherderite on albite | image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Hoping to Have Some Herderite of Your Own?

Most people don’t know about herderite, but now that you’ve herd about it, you’ve got a leg up on them! This beautiful, rare gem may be hard to find, but it’s a unique treasure in warm to cool colors that suit any taste.

Buy herderite gemstones today!