Legrandite Gemstone: Properties, Meanings, Value & More

Legrandite is an unusual gemstone mostly known among collectors. It’s sought-after for its vibrant coloring and attractive crystal habits.

What colors does legrandite come in? The best-known legrandite mineral color is bright yellow, but it can also be lighter to deeper yellow shades or even colorless.

In terms of rarity, legrandite is a rare mineral and even rarer gemstone. It’s very rarely faceted.

Still, many collectors praise this crystal as remarkable! Today, we’ll go over why that is as we explore legrandite’s uses, properties, prices, history, and more. We’ll also go over how to handle legrandite safely.

Pictured above: Intense yellow legrandite thumbnail crystal | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

What Is Legrandite?

Legrandite is a very rare semi-precious gemstone beloved for its lemon-yellow hues, scarcity, and stunning crystal shapes.

Nearly all of the top-quality legrandite specimens come from Mapimi, Mexico. One of the most famous is nicknamed the “Aztec Sun,” a specimen with two crystal clusters creating fan-like sprays in opposite directions. The “Aztec Sun” is claimed by some to be the best legrandite ever discovered.

Astrologically, legrandite is used as a lucky talisman for those born under Scorpio.

Outside of aesthetic or astrological purposes, legrandite’s uses industrially are little to none. Although zinc arsenate can be used in wood preservatives and insecticides, legrandite is too rare to serve as a source of these elements.

However, the mineral has been researched for insight into its mineralogy, like the type of hydrogen bonding that gives it structural stability.

Speaking of its mineralogy…

Legrandite Specifications & Characteristics

As a hydrated zinc arsenate hydroxide, legrandite’s formula is written as Zn2(AsO4)(OH)·H2O. This formula is almost the same as that of adamite and paradamite, but the number of water molecules differs.

The first legrandite material analyzed (for the mineral’s original description) had iron partially replacing zinc, along with traces of manganese.

Most legrandites are found as sprays or sheaf-like aggregates (parallel groupings resembling bundles) of elongated, prismatic crystals. They’re often striated parallel to {001}, {111}, {100}, and {001}.

Legrandite’s structure is distinct in having proton transfer tunnels along its crystal axes. The mineral has three types of hydrogen bonds, and these bonds’ interactions give legrandite structural stability.

Here are legrandite properties listed:

• Mohs hardness: 4.5

• Color: Shades of yellow (including yellow-green, golden-yellow, and brownish-yellow) or colorless

• Crystal structure: Monoclinic

• Luster: Usually vitreous; Can be sub-vitreous, resinous, or waxy

• Transparency: Translucent to transparent

• Refractive index: 1.675-1.740

• Density: 3.98-4.04

• Cleavage: Imperfect/fair to poor on {100}

• Fracture: Uneven/irregular

• Streak: White

• Luminescence: None

• Pleochroism: Present, colorless to yellow

• Birefringence: 0.060

• Dispersion: Distinct

That’s enough mineralogy for now, so let’s switch gears to peek into legrandite’s metaphysical side.

Pictured above: Old legrandite specimen (1950s or earlier) from Flor de Peña Mine, Mexico | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Legrandite Meaning & History

As a fairly modern stone, only discovered in the past 100 years, legrandite doesn’t have much folklore. But it still has a devoted following among spiritual crystal users.

This yellow gem is associated with the sun, symbolizing vitality, energy, and joy. Other interpretations of legrandite’s meaning is that it represents harmony and enlightenment.

History

The first description of legrandite was published in 1932, co-written by Belgian mineralogist Julien Drugman and English analytical chemist & mineralogist Max Hutchinson Hey.

The men named it “legrandite” after Belgian mine manager and mineral collector, Louis Charles Antoine Legrand, who had collected the first specimens from the Flor de Peña mine in Nuevo Leon, Mexico, probably sometime in the early 1900s.

Unfortunately, Legrand passed away in 1920. A few years before the 1932 description, Drugman had received a parcel of specimens from Legrand’s widow, one of which was a “massive blende” with transparent, bright yellow crystals Drugman couldn’t identify.

Hey conducted a chemical analysis and found it was a new mineral, specifically a “basic zinc arsenate.”

The Flor de Peña mine is actually quite small. It’s only known for being legrandite’s type locality.

In the 1960s, a more important Mexican source of legrandite was discovered: the Ojuela mine. The world’s top legrandites have been mined from Ojuela sporadically since then.

Pictured above: Rare legrandite specimen attached to olive-green and brown botryoidal smithsonite; Found in Nuevo Leon locality; From Consie Prince Collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Legrandite Healing Properties

As a famously yellow healing stone, legrandite reflects the joyful, clarity-bringing, and creativity-boosting properties of other yellow gemstones.

Physical Healing

Crystal healers claim legrandite’s metaphysical properties include treating issues related to:

• Low energy or burnout

• Digestion

• Reproductive health

• Blood pressure

• Heartburn

• Ulcers

Emotional Healing

Emotionally, legrandite is most commonly used for boosting creativity and confidence. Crystal healers also recommend these yellow healing crystals for facilitating more effective self-expression, helping release negative energies (both internal and external), and promoting spiritual awareness.

Additionally, legrandite is believed to help enhance the best parts of your personality, improve your focus, and lower stress.

Chakra Healing

Chakra healing is the process of resolving negative symptoms associated with an energy center (chakra) being blocked. The goal is to open the chakra so energy can flow freely through it again.

Legrandite is a solar plexus (navel) chakra stone. Located right below the breast bone, this chakra governs personal growth, self-image, and purpose.

Common signs of a blocked solar plexus chakra are feelings of insecurity, detachment from yourself, or loss of control. Once you open the blocked chakra with legrandite, you may feel greater self-respect, confidence to express your ambitions, and emotional harmony.

Pictured above: Cockscomb spray of gemmy, lemon yellow legrandite crystals wrapped around bar of gossan matrix; From Ed Ruggiero Collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Legrandite Gemstone Properties

Besides rarity, legrandite gemstone value depends on color, cut, clarity, transparency, and carat weight. Currently, there aren’t any known treatments or synthetic options for legrandite.

Color

Legrandites are usually found in shades of yellow, from pale to vibrant or even deep, sometimes with orange, green, or brown undertones. Typically, the coloring is splotchy, with colorless areas.

The yellow coloring may come from ferrous iron that oxidized.

The most valuable and sought-after legrandites have uniform, vibrant lemon-yellow or golden-yellow coloring.

Cut

Facetable rough is scarce, making faceted legrandite rarer and more valuable. Faceted legrandite gemstones are almost always yellow, often with long rectangular or baguette shapes. They can also have pentagonal, lozenge, or triangle shapes.

Most legrandite available is rough (uncut), with larger, more attractive specimens commanding higher prices.

Clarity & Transparency

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

Potential inclusions in legrandite include:

• Limonite

• Feathers

• Incipient fissures

• Fingerprints

Transparent legrandite stones (which are already rare) with fewer visible inclusions are quite valuable, especially when faceted.

Carat Weight & Size

Some faceted legrandite gems are 2 to 4 carats, but it can be hard to find even small, 1-carat faceted legrandites. Almost all faceted legrandites for sale are under 1 carat.

For rough crystals, transparency usually decreases as size increases, so any transparent legrandite crystals in larger sizes command high prices.

Pictured above: Two 2-cm legrandite crystals (with areas of damaged legrandite around them) in limonite matrix | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Legrandite Formation & Sources

Legrandite minerals form as secondary minerals when primary minerals in zinc and arsenic deposits are oxidized, altering into secondary minerals like legrandite, smithsonite, or adamite.

Part of legrandite’s rarity comes from the fact that it can only form stably with a specific, delicate balance of arsenate and zinc.

The mineral is found in limestone, superficial oxidized zones of zinc-arsenate deposits, and rarely, granite pegmatites.

Minerals commonly found associated with legrandite are:

• Adamite

• Paradamite

• Köttigite

• Scorodite

• Smithsonite

• Leiteite

• Renierite

• Pharmacosiderite

• Aurichalcite

• Goethite

• Pyrite

That covers the geological side, but where is legrandite found geographically?

Mining Locations

As you know by now, the best source of legrandite is the Ojuela mine in Mexico. Additionally, Mexico is the only known source of facetable legrandite rough.

Additional significant sources of attractive legrandite specimens are:

• Brazil

• Japan

• Namibia

• USA (New Jersey)

Sources aside, how much can you expect to pay for legrandite?

Pictured above: Legrandite crystal spray with iridescent golden color; Formerly in John Barlow's collection | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Legrandite Price & Value

Perhaps unsurprisingly, faceted options have the highest legrandite gemstone price per carat. These range from around $1,600 to $6,600 per carat or about $170 to $1,650 total — remember, many of these are under 1 carat.

Rough legrandites vary in price extremely broadly, from $20 to $15,000. Almost all of these are legrandites on a matrix.

The most expensive options, about $400 to $15,000, are usually large, damage-free, and top-quality.

Individual, gemmy crystals with bright yellow coloring range from around $70 to $3,500.

Legrandite Care and Maintenance

First and foremost, legrandite is a hazardous mineral with high toxicity risk because of its arsenic content, particularly if the arsenic is ingested.

As such, don’t use legrandite in jewelry, as it can be scratched and release arsenic-containing particles. Anyone cutting legrandite should practice the highest safety precautions.

Display or store legrandite safely by keeping it separate from other gems and away from children or pets.

For gemstone care, keep legrandite away from harsh chemicals. You clean legrandite (wearing safety gear like gloves, goggles, and a mask) with warm water, mild soap, and a soft toothbrush.

Pictured above: Legrandite thumbnail with great pedigree (box and label from Willard "Perky" Perkin collection) | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Let the Sunshine in With Legrandite!

Legrandite is like sunshine in gemstone form, whether it’s used for decoration, healing, or otherwise. With an added dose of rarity, gorgeous formations, and unusual appeal, legrandite belongs in any gem enthusiast’s collection!

Buy legrandite gemstones today!