Ekanite Gemstone: Properties, Value, Rarity, and Safety

Ekanite is a rarely occurring, naturally radioactive mineral that can occasionally resemble a gemstone. It can be very fragile and unstable due to damage to its crystal structure as a result of its radioactivity and its rarity makes it too unusual to determine a default price.

It appeals to collectors because it’s odd. The idea that a crystal is slowly destroying its own internal structure isn’t common in even the rarest minerals and can be cut into straight green or yellow-green gemstones.

Three questions come up most. Does it cost a lot?  There’s the thing about quality, and there’s no stable comparison for the price. Is it risky? That depends on the specimen and how you handle it. Can you wear it? Occasionally and carefully at most, and not as a daily piece. The sections below explain why.

Quick Answer:

Ekanite gemstone is a rare form of radioactive thorium silicate found in the gem gravels of Sri Lanka. Sometimes the material is metamict (amberised) due to alteration of the crystal structure by radiation. Colour is not an indication of the safety of the material – it’s the actual radiation, not what you can see. Hardness 4.5 to 5.

What Is Ekanite?

Ekanite gemstone is a calcium thorium silicate with the ideal formula Ca₂ThSi₈O₂₀. Natural specimens often include some uranium, iron, manganese, or lead. The GIA categorizes it as a phyllosilicate, and its Strunz classification is 9. EA.10.

In its original, undamaged form, ekanite is tetragonal. Most gem material is no longer in that state, which I’ll explain in the metamictization section.

Ekanite Mineral Name, Formula, and Group:

In memory of F.L.D. Ekanayake (Sri Lankan gemologist). Mindat and GIA both credit him with first recognizing the material. A published study by Anderson and colleagues in 1961 described it as a new metamict mineral from Ceylon.

Thorium makes up roughly 24 percent of the mineral by weight, according to GIA’s 2022 feature on ekanite. That thorium is the source of the radioactivity.

Who Discovered Ekanite?

Ekanayake came across the stuff in Sri Lanka during the early 1950s and suspected that it was something entirely different. It was dull dark green rough. When cut as a cabochon, it showed a four-rayed star, which got people’s attention.

It was formally described in 1961. The type locality is Eheliyagoda in the Ratnapura District of the Sabaragamuwa Province of Sri Lanka.

Why Is Ekanite Considered Rare?

Ekanite gemstone is rare in two different ways, and people mix them up. The mineral itself is uncommon. Gem-quality, cuttable material is rarer still.

GIA says ekanite is a rare mineral in Sri Lanka’s gem gravels. When it does turn up, it often shows gem characteristics. Even so, most pieces are included or cloudy, and clean stones above a few carats are hard to find.

I wouldn’t call it “the rarest gemstone.” That claim needs a measurement nobody has. Rare mineral and rare gem-quality material are different things, and ekanite shows why.

Ekanite Gemstone Properties and Identification:

Ekanite gemstone is soft, brittle, and optically anisotropic. The numbers below are from published mineral facts, but will be variable as the material is altered by radiation damage. Consider all figures to be approximate rather than absolute.

Formula	Ca₂ThSi₈O₂₀ (ideal)	Mindat, GIA
Crystal structure	The stone has Tetragonal (ideal); often metamict	Handbook of Mineralogy
Mohs scale	About 4.5 to 5	Handbook of Mineralogy
Specific gravities is about	2.95 to 3.28 measured; about 3.27 to 3.32 in gem material	Handbook of Mineralogy; Nasdala et al. 2017; gemdat.org
Refractive index is  about	ω 1.580, ε 1.568 (non-metamict); about 1.593 to 1.597 (metamict)	Handbook of Mineralogy; gemdat.org
Primary colors	Green, yellow-green, yellowish brown, straw-yellow; red from inclusions	Handbook of Mineralogy
Cleavage	Distinct on {101}	Handbook of Mineralogy
Radioactivity	Thorium-bearing, with minor uranium	GIA 2022
Main locality	Sri Lanka	Mindat, GIA

I haven’t listed dispersion or pleochroism. I couldn’t verify reliable values, and I won’t guess.

Ekanite Gemstone Color and Appearance:

Normal colors range from yellow-green to greenish yellow and yellowish brown. Pure material is straw yellow. Dark red to brown colors are often due to inclusions, not ekanite itself.

Inclusions are common in most specimens, and clear, transparent gemstones are the exception. Cut stones have been reported up to about 25 carats, but that’s a ceiling, not something you’ll see on a dealer’s table.

Rough ekanite gemstone from Sri Lankan gravels has an unusual look. GIA notes that most specimens aren’t water-worn pebbles, which is odd for gravel deposits. They keep a distinctive surface texture, and sometimes concave features.

Ekanite Gemstone Hardness and Durability:

This hardness was about 4.5-5 on the Mohs scale. Slightly softer than quartz, softer than nearly all gemstone ring stones, and within a point of apatite.

Mohs hardness gives marginal information. Ekanite gemstone was brittle and showed cleavage in one direction. Radiation damage also leaves some material with internal stress, so one piece can behave differently from the next. I’d never trust a hardness number on a metamict stone the way I would on a clean sapphire.

Ekanite Gemstone Refractive Index and Optical Properties:

Undamaged ekanite is doubly refractive, with indices of about 1.580 and 1.568. Metamict gem material behaves like a glass. It’s singly refractive, with an index of roughly 1.593 to 1.597.

That’s why published numbers disagree. They aren’t describing the same state of the crystal. If a lab report shows a single refractive index near 1.59 to 1.60, that fits metamict ekanite, but it doesn’t prove identity by itself.

Ekanite Crystal Structure and Metamictization:

“Metamictization” – the crystal is eaten away by radiation, either over hundreds of millions of years or when the uranium and thorium have decayed so much that the radioactive atom shatters, destroying the lattice or surrounding area. It loses all shape and becomes amorphous.

Ekanite gemstone from Okkampitiya in Sri Lanka has been studied for this. Researchers found a chemical composition of about Ca₂Th₀.₉U₀.₁Si₈O₂₀ in a fully metamict state. The same study dated the material at around 560 million years.

One more point for buyers. GIA reports that attempts to improve ekanite with heat treatment have invariably failed. So I’d treat a seller who claims a heat-enhanced ekanite with suspicion.

How Radioactive Is Ekanite?

Ekanite gemstone itself is radioactive, because it contains thorium (with minor uranium). There is no honest article that can give you one safe or unsafe dose number, as it depends on the specimen, how big it is and how you handle it. It is measurable, not visible.

Why Ekanite Contains Radioactive Elements?

Thorium is part of ekanite’s structure. The Handbook of Mineralogy states that the mineral emits alpha, beta, and gamma radiation. These radiations are produced by the decay chains of thorium and uranium present in the mineral.

The same process that causes metamictization also makes the stone radioactive. Radiation damages the crystal, resulting in the stone becoming radioactive.

Does Every Ekanite Specimen Have the Same Radiation Level?

No. Composition varies. Uranium content varies. Size and shape change how much radiation reaches you. A small, cut stone and a large rough chunk won’t read the same.

Looks don’t mean a thing here. A shiny, clean green stone and a dull brown one can read very differently, or very similarly. Only a calibrated instrument can return a number.

Is Ekanite Dangerous to Handle or Keep at Home?

I won’t say “completely safe” or “always dangerous.” Both claims are incorrect for different reasons.

Imagine three different things. External exposure is exposure from the stone. Contamination is exposure from particles on your hands or other surfaces. Internal exposure is exposure from your breathing or ingestion of dust.

Dust is the one I really try to pay attention to. When you cut, grind,  sand or crumble stone, it may spit off dust.  But you should take extra precautions and have good dust collection. Crumbling stone calls for caution.

For storage, I’d put it in a sealed container and keep it out of places where people will be sitting around for long periods of time. Don’t put it in the bedroom and don’t leave it on your desk (or put it on your desk and push your chair in). And see if you have a lot of it from a licensed radiation safety officer.

Can Ekanite Gemstone Be Worn as Jewelry?

GIA’s 2022 article says ekanite’s radioactivity makes stones unsuitable for setting in daily-worn jewelry, though it notes that different assessments exist. I take the cautious side.

My own rule is simple. I would wear ekanite only occasionally, never every day. I’d check its radiation level first and store it safely when it’s not in use. Anyone who sells set ekanite should be able to tell the buyer what the stone is and what the readings were.

Where Is Ekanite Gemstone Found?

Ekanite gemstone comes mainly from Sri Lanka, where it occurs as detrital material in gem gravels. The type locality is Eheliyagoda in Ratnapura District. Additional Sri Lankan references are Okkampitiya of Uva Province and Ellawala of Sabaragamuwa Province.

Ekanite gemstone has also been reported from Mont Saint-Hilaire in Quebec and from the Tombstone Mountains in Yukon outside Sri Lanka where it was found in a glacial boulder. It also appears in volcanic ejecta in Italy’s Alban Hills. Mindat and Wikipedia also list Russia.

For buyers, Sri Lanka is where gem-quality material mostly comes from. GIA says it’s still commonly traded in the Sri Lankan gem market, despite the radioactivity.

There are two reasons why locality is important. It is of interest in confirming the authenticity of the stone and, even more obviously, because it influences its mode of formation, and this is important to collectors and scientists.

Ekanite Gemstone Price, Value, and Market Availability:

I can’t give you a trustworthy price per carat for ekanite gemstone, and anyone who does should show you completed sales. Published prices are mostly asking prices, which aren’t the same as what stones actually sell for.

How Much Does Ekanite Cost?

Ekanite gemstonee prices vary by seller, origin and quality. I deal with sellers from different origins, and their pricing structures differ. That matches what I’d expect for such a thin market.

Four price types get mixed up. Asking prices are what sellers hope to get. Completed sales are what buyers paid. Specimen prices reflect crystal or rough interest. Faceted-gem prices reflect color, clarity and cut.

Ekanite Gemstone Price Per Carat:

A reliable benchmark is not available. I haven’t found recent, verifiable sales data I’d publish. Mineral databases may show a stone’s weight and photo, but that doesn’t give you a price.

If you see “ekanite gemstone price per carat” quoted as a fixed number, ask where it came from. A thin market with few sales and wildly different qualities can’t support one number.

Ekanite Gemstone Price in Sri Lanka:

Local pricing in Sri Lanka depends on the dealer, the quality, and the paperwork. Currency and provenance matter. Published figures rarely tell you whether a stone was identified, measured for radiation, or documented.

Let’s just say I’d use one Sri Lankan price as data, not a rule. Get a few quotes on other pearls of the same size and quality, and then decide.

What Affects Ekanite Gemstone Value?

Quality drives price more than the species name. These factors count:

• Color and how evenly it’s distributed
• Clarity and the amount of inclusions
• Cut quality and how much weight survived
• Size, since clean larger stones are scarcer
• Condition, including cracks and crumbling
• Documented origin
• Radiation measurements and safety paperwork

Research significance adds interest for some collectors. Safety considerations can reduce the buyer pool, and that affects resale.

Is Ekanite for Sale, and Who Buys It?

Where to get Ekanite gemstone can be found in some mineral shops and from some gem dealers. Customers for Ekanite can include collectors, mineral enthusiasts, and fans of unusual stones.

I research safety and import/export regulations. Shipping radioactive materials is subject to regulation, and regulations differ by country and airmail carrier.  Do not make assumptions about a package clearing.

Ekanite Uses, Benefits, and Meaning:

Ekanite’s real uses are collecting and research. Scientists have used it to study radiation damage and to date rocks, since uranium-lead dating has been applied to Sri Lankan material.

As for meaning, I don’t know of a long-established spiritual tradition around ekanite. Any zodiac, healing or energy claims you see are modern beliefs at best. I treat them as personal belief, not fact, and I wouldn’t promise any benefit.

Health claims deserve extra caution. Telling someone a radioactive stone will heal them is the opposite of responsible. Don’t buy ekanite for that reason.

Ekanite Jewelry and Rings: Is It a Practical Choice?

There are two reasons why Ekanite gemstone is not suitable for daily wear jewelry. It is a soft and fragile material, and it contains radioisotopes.

Rings get beat up with 4.5 – 5 hardness and obvious cleavage. When your ring hits the counters and door handles and keys all day long. Chips and scratches are inevitable.

That is unrelated to the radiation. GIA says these stones are not for use in jewelry for daily wear.  The ring is in contact with skin for hours.

If someone still wants a piece, I’d suggest occasional wear only, a protective setting, a radiation reading and clear disclosure at sale. For most buyers, a display case is the better home.

How to Identify Ekanite?

You cannot identify a specimen of ekanite gemstone by observation alone,  in hand or photographs. There are numerous other minerals and gems with related colors, and the unique characteristics of this sample require instrumentation.

A lab or a gemologist in the know will look at it for:  refractive index, specific gravity, spectra, and sometimes chemistry. The metamict ekanite has a single refractive index that goes between 1.59 and 1.60 and a specific gravity of around 3.3. Those values are fine but nothing special on their own.

Radioactivity is a clue, not a proof. Other minerals are radioactive too, including metamict zircon. A radiation reading can point toward ekanite or away from a simple lookalike, but it doesn’t confirm species.

Ask the seller four questions:

1. How was the stone identified?
2. Was its radiation level measured, and what were the readings?
3. Is the origin documented?
4. Can it legally ship to my country?

Also ask about damage, inclusions and treatment. Given GIA’s note that heat enhancement attempts fail, a “treated ekanite” claim needs evidence.

Image-based identification tools can’t confirm ekanite, and they can’t detect radiation. Use them, if at all, only as a rough starting point.

Ekanite Compared With Similar Minerals:

It can be confused with everyday green and yellow stones and has its metamict behavior in common with other minerals. Comparing them can be useful.

• Zircon: Metamict zircon is the best-known gem that also suffers radiation damage. Zircon is much more common in the trade. Ekanite is far scarcer and has a higher thorium content.
• Common green stones: Tourmaline, peridot, apatite and similar stones can resemble ekanite in color. They aren’t radioactive in any meaningful way, and they’re easier to identify.
• Additional Thorium Minerals: Many thorium minerals are known, some of which are associated with ekanite.  Most are opaque or small in size and not used as gems.
• The big difference for buyers is simple: With most green stones, you worry about quality and price. With ekanite, you also worry about identity and safety.

The Biggest Buyer Misconception:

Most buyers treat ekanite like a normal gemstone. They expect a fixed price per carat, easy resale and daily wear. That’s the mistake.

What holds true is different. Ekanite gemstone is a radioactive, metamict mineral with a very limited market.  It only has value if it has quality, documentation, measurements and it is a complete risk to keep it on all day long.

It matters because buyers who skip inspection can end up with misidentified, undocumented or hard-to-ship material. I’d rather you spend on testing than on regret.

Buyer Checklist:

• Is the Ekanite gemstone identified by a lab or experienced gemologist?
• Has its radiation level been measured?
• Is the origin documented?
• Does it legally ship to your country?
• Is Ekanite gemstone intact, or cracked and crumbling?
• Are there heavy inclusions?
• Is any treatment claim backed by evidence?
• Does the price reflect quality, not just the word “rare”?
• Do you have a safe place to store it?

FAQs:

Conclusion: Is Ekanite Worth Collecting?

Ekanite gemstone is a collector’s piece if you love geology and live with the burden of knowledge. It is unique,  peculiar, and has a living science behind it, but do not buy it on a whim.

Buy certified stones, test the radiation, pack them securely,  and look into shipping regulations. Don’t get involved with the claims of spirituality and the brag about price per carat. If those boxes are checked, ekanite is definitely one of the coolest stones you can have

This content is published by gemstone expert and enthusiast KamilHussain!