What is Carletonite? A thorough explanation of the “mysterious blue mineral” that can only be found in one place in the world
RARE MINERAL FILE — Rare mineral encyclopedia
What is Carletonite?
What is Carletonite?
Can only be found in one place in the world
A thorough explanation of the “phantom blue mineral” Complete illustrated guide to mineral data, formation mechanism, selection, and care
Carletonite (Japanese name: Carletonite)is in the worldThe only place in Mont Saint-Hilaire, Quebec, CanadaIt is an extremely rare silicate mineral that has been confirmed to be produced only in Japan. The most attractive features are the deep blue that draws you in and the ``color zoning'' in which layers of color appear within the crystal. In this article, we will provide an easy-to-understand explanation, supervised by experts, with abundant illustrations, from basic information about minerals to how they are produced, how to select and care for them.
*About the notation:「cartoleniteAlthough it is sometimes written as ``Carletonite'', it refers to the same mineral as the English name Carletonite. In this article, we will use the official notation "Carletonite".
What is Carletonite? Check the basic data first
Carletonite was discovered in Canada in the late 1960s.Officially listed as a new mineral in 1971It is a relatively new mineral. The discoverer, mineralogist G. Y. Chao, learnedCarleton University (Ottawa)It was named after. A type of layered silicate (phyllosilicate) mineral, it has been pointed out that it is related to apophyllite (fisheye stones).
[Figure 1] Basic data of carletonite
The origin of the name is "the name of the university"
Mineral names are often derived from the place of origin or the name of the discoverer, but carletonite is a little different. Mr. Chao, the discoverer, was employedNamed in honor of Carleton University in Ottawa, CanadaIt was done. The name itself is engraved with the fact that this stone was born from a place of academic research.
“Square pillar” crystals created by the tetragonal system
carletonite crystalstetragonal systemIt belongs to , and grows in the shape of a column with a rectangular cross section. in the big onesCrystals reaching 6cmAlthough it has been reported, most of the ones you see on the market are between a few mm and 1 cm. It has a complete cleavage in the direction of the base, so care must be taken when handling it.
[Figure 2] Mechanism of tetragonal system and image of columnar crystals
Carletonite Quick Reference Chart at a Glance
| Comparison items | carletonite |
|---|---|
| Production area | 1 location in the world (Mont Saint-Hilaire, Canada, Poudrette Quarry) |
| mohs hardness | 4-4.5 (softer than glass) |
| Distribution form | Mainly raw stones and mineral specimens with host rocks/very few loose ones |
| Gem quality production | Very few (only a few transparent crystals can be polished) |
| Popularity as a specimen | ★★★★★(“Phantom Blue” coveted by collectors) |
| For jewelry | ★☆☆☆☆(For ornamental/collection purposes) |
What is Mont Saint Hilaire, the only production area in the world?
When talking about the rarity of Carletonite, it is essential to know where it is produced. The production is confirmed to beThe only Poudrette quarry in the world, located in Mont Saint-Hilaire, Quebec, Canada. Mont Saint-Hilaire is known worldwide as a ``sacred place for minerals,'' with over 400 types of minerals and dozens of new minerals discovered here.
[Figure 3] The only production area in the world: Mont Saint-Hilaire, Canada
Overwhelming rarity brought about by “limited to one production area”
While diamonds and sapphires come from multiple mines around the world, carletonite isThere is only one supply source on earth. Moreover, the supply of new specimens is limited due to the operating conditions of quarries, and it is said that it is becoming harder to obtain high-quality crystals year by year. This is why it is called the "phantom blue mineral" among collectors.
POINT：For minerals that are produced in only one region, the market value is directly linked to the conditions of that region (mining suspension, access restrictions, etc.). Carletonite can be said to be a stone that is more collectible than speculative in that "almost all the inventory in the world is currently available."
How carletonite is produced [illustration]
Carletonite is born in a special rock environment created by magma. The stage isNepheline syenite (nepheline cyanite)A rare intrusive body of alkaline igneous rock. Masses of shale and limestone (xenoliths = xenoliths) incorporated there are metamorphosed by the heat of magma.hornfels or siliceous marbleIt is believed that carletonite crystallized within it.
[Figure 4] Special environment created by thermal metamorphosis of magma (schematic diagram)
Generation process in 3 steps
[Figure 5] Three steps of generation process
How special this condition of ``alkaline igneous rock x thermally metamorphosed xenolith'' is is demonstrated by the fact that carletonite has not been found anywhere else in the world except Mont Saint-Hilaire. It is truly a miraculous mineral that was created through a series of geological coincidences.
The charm of color and crystals: color zoning and phantoms
The biggest highlight of Carletonite is thatcolorIt is. In addition to blue crystals ranging from light blue to dark blue, pink, white, and colorless crystals are also produced. The cause of blue color is not impurity elements,"Hole (electron loophole) defect" that occurs in carbonate ions in crystalsThis is also a rare coloring mechanism.
"Color zoning" where layers of color appear in a single crystal
In carletonite crystals, as a remnant of the environmental change during the growth process,Color zoning where shades of color appear in bands or layersis frequently seen. The center is dark blue and the outside is light.Phantom (phantom crystal)Collectors enjoy this "story of color".
[Figure 6] Two patterns that create layers of color
SELBY buyer's perspective:We have seen several Carletonites at our store,No two individuals had the same color or zoning.. I feel that the value of this stone lies in the individual differences between the dark blue layers, some with sharp transitions, and others with mist-like gradations.
📷 Photo insertion space: Enlarged photo of specimen showing zoning*If you include a close-up photo of the specimen you actually handled, it will be effective for both Google image search and E-E-A-T.
Pleochroism: the color changes depending on the viewing angle
Weak against carletonitePleochroism (pleochroism)Depending on the direction in which the crystal is viewed, a change in color from very pale blue to pale pink may be observed. The real thrill of this stone is that when you carefully observe it with a magnifying glass, you can see the uniqueness of each specimen.
How to tell the difference between similar stones
There are several rare blue minerals, and some can be easily confused based on their appearance. We have organized the differences between typical "similar stones".
| Mineral name | Relationship/Characteristics | Distinguishing points from Carletonite |
|---|---|---|
| fluorocaletonite | A "sibling mineral" with a predominance of fluorine. Recently described in Russia. | The appearance is very similar. It is difficult to make a precise distinction without chemical analysis;Country of origin information (whether produced in Canada or not) is an important clue。 |
| Apophyllite (fisheye stone) | Also a closely related group of layered silicates. Quadrilateral columnar crystals are similar. | Apophyllite is mainly colorless to green and is produced from all over the world.If it is a dark blue columnar crystal, it is most likely carletonite.。 |
| Blue minerals such as afghanite and lazurite | Dark blue color is common. | Comprehensive judgment of crystal shape (square prism), type of host rock, fluorescence, etc.We recommend identification at a specialty store.。 |
[Figure 7] Comparison image with similar minerals
Attention:Carletonite has a low distribution volume and tends to be expensive, soCheap products with no mention of origin or mineral nameBe careful. You can feel safe purchasing from reliable mineral specimen specialty stores and sellers that clearly display identification information.
What is gem quality carletonite (loose)?
Most of the carletonites on the market are raw stones and mineral specimens with host rocks attached.A small number of crystals have high transparency and are suitable for facet cutting.also exists. However, it is extremely soft with a Mohs hardness of 4 to 4.5, and has a perfect cleavage in one direction.There are only a limited number of craftsmen in the world who can polish.。
Therefore, gem quality carletonite loose isRare than mineral specimensIt is highly valued in the collector market. Most of the cut stones are small, up to around 1 carat, but the loose ones with their deep blue color are the perfect ``portable Mont Saint-Hilaire.'' This is a stone that can become the core of a rare stone collection.
📷 Photo insertion space: ① Specimen with rough stone/host rock ② Pre-cut loose ③ Processing example of rings etc.*Ideal is a line-up photo that conveys the flow of "rough stone → loose → jewelry" in one photo.
Point of view when choosing a route
What to focus on in RuthBalance between “color intensity” and “terri” (how to shine)It is. Even if the color is dark, if there are many inclusions or cracks (scars caused by cleavage), there is a risk of durability, so it is essential to check enlarged photos and the actual item. In addition, it is difficult to distinguish from the aforementioned fluorocaletonite by appearance, soIs there a purchasing route that can confirm the origin of the product?is the difference between reliability.
SELBY buyer's perspective:From the point of view of on-site inspection of production areas around the world and direct import, loose carletonite is not a stone that can be found by looking for it.“The best time to buy this stone is when you come across it.”It is. Even in our information network with overseas rare stone collectors, we only hear about high-quality cut stones a few times a year.
We import rare stones from around the world directly from their production areas.
SELBY handles rare loose stones purchased directly by jewelry buyers locally.
Please search our collection for a once-in-a-lifetime encounter with rare stones.
How to choose Carletonite and its price range
Carletonite is mainly"Rough stone/specimen with host rock"It is extremely rare to find a cut loose piece that is distributed as such. Here, we will focus on specimens and summarize the points that affect value and the approximate price.
Four checkpoints to determine value
[Figure 8] 4 items to check when choosing
Price guideline
| grade | Features | Estimated price |
|---|---|---|
| Small specimen with host rock | Crystals or lumps of several mm in size. For beginners. | Around 5,000 to 30,000 yen |
| High quality crystal specimens | The blue color is deep and the columnar crystal planes are clear. 1cm class. | Around 30,000 to 100,000 yen |
| gem quality loose | Transparent crystal that can be faceted. Very few. | 100,000 yen or more |
*The above is just a guideline. carletonite priceA stone that is limited to one production area and whose supply has almost stopped.Due to its nature, it varies greatly depending on the distribution situation. It is not uncommon for there to be several times the difference in the depth of color and beauty of zoning even within the same grade. When purchasing, we recommend comparing products at multiple specialty stores.
For beginners:It is recommended to start with a "small specimen with host rock". The appeal of carletonite is that its blue color stands out due to the contrast with the host rock (hornfels), and you can enjoy its occurrence (the environment in which it was grown).
Care and storage method: Precautions because it is a soft stone
carletoniteMohs hardness is 4-4.5. It is softer than glass (approximately 5-5.5) and hard enough to be scratched with a knife. Furthermore, because it has a complete cleavage in one direction, it has the property of being easily broken by impact.
[Figure 9] Positioning on the Mohs hardness scale
4 care and storage rules
[Figure 10] 4 rules for care and storage
I would like to pay special attention toContact with other hard stonesIt is. If you put it in the same box as crystal (hardness 7), it will easily get scratched. Store specimens individually in pedestal cases or compartment boxes, and wrap them in soft paper or cloth when transporting them.
Meaning and legend as a power stone
Carletonite is a mineral with a short history, so there is no ancient legend, but in the world of power stones, it is commonly known as a deep blue stone."Expressiveness" "Intuition" "Quietness of mind"It is popular as a stone that symbolizes. It is said to correspond to the chakra between the throat and eyebrows (throat chakra/third eye chakra), and it is said to support the ability to express one's thoughts into words and the ability to concentrate and look at things.
[Figure 11] Image of stone words
※The meanings and effects of power stones are not scientifically proven, but are based on cultural legends and images. Please enjoy it as a talisman.
Frequently asked questions (FAQ)
About name and rarity
QWhat is "Cartrenite"? Is it the same stone as carletonite?
It's the same mineral. "Cartolenite" is a spelling variation of the English name Carletonite, the official katakana spelling is "Carletonite", and the mineralogical Japanese name is "Carletonite". You can find information on the same stone no matter which way you search.
QWhy is carletonite so rare?
The only place where it is confirmed to be produced is the Poudrette quarry in Mont Saint-Hilaire, Quebec, Canada. It is a mineral that is only produced under special geological conditions (thermal metamorphosis of xenolith incorporated into alkaline igneous rock), and because new supply is limited, there are extremely few minerals on the market.
QWhat is the difference from fluorocaletonite?
They are "sibling minerals" with a predominance of fluorine (F), and they look exactly like two melons. Chemical analysis is required to make a precise distinction, so in actual buying and selling, the most important clue is to confirm the origin, ``where it was harvested.''
About color and properties
QWhy is carletonite blue?
It is thought that the cause is "hole (electron loophole) defects" that occur in carbonate ions in the crystal. This mechanism is rare among blue gemstones, which often develop their color due to impurity elements such as iron and titanium.
QWill the color change with ultraviolet light (sunlight)?
It has been pointed out that the color resulting from defects may change under the influence of strong light or heat. As a precaution, we recommend storing in a dark place at room temperature, avoiding direct sunlight for long periods of time.
QDoes carletonite fluoresce?
The clear and strong fluorescence of carletonite itself is not generally known. However, many minerals from the Mont Saint-Hilaire region fluoresce under ultraviolet light, and symbiotic minerals may glow when exposed to UV light in specimens with host rocks. This is one of the fun ways to observe specimens.
QAre you sensitive to water? Is it okay to wash it?
Although it is not a stone that easily dissolves in water, it has low hardness and may cleave, so avoid washing it with water, soaking it in water, or cleaning it with ultrasonic waves. The basic cleaning method is wiping with a dry, soft cloth.
About loose jewelry
QCan it be polished into loose (bare stone)?
There are examples of highly transparent crystals being faceted. However, since it is soft with a hardness of 4 to 4.5 and has perfect cleavage, it is extremely difficult to polish, and there are only a limited number of craftsmen who can handle it. As a result, gem-quality loose gemstones are even rarer than mineral specimens.
QCan it be worn every day as jewelry?
Not recommended. It is not suitable for jewelry such as rings and bracelets that are likely to get bumped on a daily basis. If you want to enjoy it, it is best to handle it carefully as an ornamental specimen, loose collection, or as a pendant top that is not susceptible to shock.
About production area and acquisition
QCan I collect the rough stones myself?
The Poudret Quarry, where it is produced, is a working quarry on private land, and as a general rule, the public is not allowed to enter or collect. The most realistic way to obtain it is to purchase it from a mineral specimen store or jewelry specialty store that has reliable information on its origin.
QCan the general public go to Mont Saint Hilaire?
The whole area of the mountain has been developed as a nature reserve and can be visited by hiking. However, the quarry area is off-limits and mineral extraction within the reserve is also prohibited. Please remember that although you can ``go see the scenery of the production area,'' you cannot ``pick up stones and return home.''
QWhat is the price range?
As a rough guide, a small specimen with host rock can cost around 5,000 to 30,000 yen, a high-quality crystal with a deep blue color and a well-shaped shape can cost around 30,000 to 100,000 yen, and a gem-quality loose specimen can cost more than 100,000 yen. As this stone is limited to one production area, the market price will fluctuate depending on the distribution situation.
QAre there any fakes? How to tell the difference?
Due to the small distribution volume, there are currently very few large-scale imitations, but caution should be taken against confusion with other minerals such as apophyllite, which have a similar appearance, and against cheap products without information on the place of origin. The best way to protect yourself is to specify the country of origin as ``Produced in Mont Saint-Hilaire, Canada'' and to purchase from a trusted specialty store.
QWhat is the most important thing to take care of?
There are three points: don't get it wet, don't rub it, and don't hit it. Basically, dry wiping with a dry, soft cloth; ultrasonic cleaning is strictly prohibited. When storing, avoid direct sunlight and store in individual cases to avoid contact with other hard stones.
Summary: Unique blue grown in one production area on earth
Carletonite isA rare mineral produced only in one place in the world: Mont Saint-Hilaire in Canada.is. The geological coincidence of magma and xenolith meeting, the mysterious blue color created by defects in carbonate ions, and the layers of color carved into a single crystal. All of them have a story that ``no two are the same.''
Because it is a delicate stone with low hardness, it is fun to handle it carefully and observe it carefully. If you ever come across one, be sure to pick up some reliable information on the production area. You should be able to see the land of Canada, 5,000km away, in the depths of the blue.
If you are looking for a once-in-a-lifetime rare stone
You can view rare stones directly imported from production areas around the world by jewelry buyers at the SELBY online shop.
Supervisor: Kozo Saito (SELBY Jewelry Buyer)
Komehei Group's only jewelry specialty company SELBY jewelry buyer. A rare stone specialist who inspects production areas around the world and directly imports loose stones. It is affectionately known as "Lethal Weapon" by local dealers and continues to share information with rare stone collectors around the world on a daily basis. He specializes in determining the authenticity and evaluating the value of rare gemstones such as Paraiba tourmaline, paudlettite, and sapphire. By disseminating gemological information, we are working to protect consumers and improve market transparency.