RARE Herkimer Diamond — 5.20 carats Exceptional clarity - NO RESERVE PRICE - Height: 11.8 mm - Width: 11.8 mm- 1.04 g - (1)

Exceptional natural Herkimer Diamond of 5.20 carats, selected for its especially imposing and balanced morphology, its remarkable transparency, and the richness of its internal architecture. This specimen has an unusual presence: its massive silhouette is structured by broad natural faces that act as windows onto its crystalline heart.

The upper part, particularly lucid, contrasts with an internal zone far more complex where growth planes, crystalline veils, microstructures, and reflective surfaces intertwine. Under directional light, these structures come to life and create a true sense of depth, as if several levels of crystallization were superimposed inside the stone.

Its compact, almost architectural shape, combined with its two natural terminations and remarkable dimensions, makes it an especially expressive piece for a mineralogical collection.

Each internal irregularity bears witness to the phenomena that accompanied its formation and directly contributes to its unique character.

The historical designation “Herkimer Diamond” here refers to a very rare two-terminated quartz specimen, sought after for its natural geometry, its glow, and the exceptional complexity some crystals can exhibit.

Characteristics

- Collection name: Herkimer Diamond
- Mineral nature: Natural double-terminated quartz
- Origin: Pakistan
- Weight: 5.20 carats
- Dimensions: 11.8 × 11.8 × 6 mm
- Morphology: Natural, double-terminated, compact and particularly balanced crystal
- Color: Colorless
- Transparency: Very beautiful transparency, punctuated by natural internal structures
- Luster: High, glassy
- Faces: Natural, broad and highly reflective
- Internal structure: Complex, with veils, growth planes, and multiple crystalline reliefs
- Particularity: Remarkable contrast between zones of great clarity and a highly structured crystalline heart
- Condition: Natural specimen for collection
- Interest: Mineralogy, crystallography, collection, and macrophotography

A remarkably balanced morphology

The first peculiarity of this specimen lies in its proportions. With 11.8 mm in length and width, the crystal has an exceptionally compact silhouette, almost equidimensional. This geometry gives it a strong visual presence despite its weight of only 5.20 carats. Its large natural faces meet at very sharp angles and construct an aesthetically striking architecture. Some appear almost perfectly transparent while others directly catch the light and become true mirrors. The crystal thus radically changes appearance depending on its orientation.

A crystalline heart of great complexity

The interior is one of the main attractions of this piece. Part of the specimen shows remarkable transparency, allowing the eye to penetrate deeply into the crystal. It gradually yields to a much more structured zone where numerous reliefs and reflective planes appear. This contrast between exterior clarity and interior complexity gives the specimen exceptional depth. To the naked eye, this architecture is already discernible. Under a loupe or macro lens, it becomes a miniature mineralogical landscape. Each change of angle reveals new structures.

Natural phenomena frozen in matter

The internal characteristics of a crystal are an integral part of its history. During growth, physico-chemical conditions in its environment can evolve. The crystal may undergo different growth phases and retain traces of these events as planes, veils, healed natural fractures, or other structures. This is precisely what makes some specimens far more fascinating than uniformly clear crystals. Here, the structures seem organized across several depths. Some become almost invisible when they do not reflect light, then suddenly appear when the crystal is inclined by a few degrees. The specimen thus has a particularly dynamic dimension.

The rarity of free growth

Double-terminated morphology requires special conditions. Unlike a crystal whose growth is directly interrupted by its matrix, a double-terminated crystal must have enough space to develop its two ends naturally. This freedom of growth gives rise to the silhouette characteristic of these specimens. When this morphology is combined with beautiful transparency, balanced proportions, expressive faces, and a particularly developed internal architecture, the result becomes much more interesting for the collector. This piece precisely brings together these elements.

A true miniature geological sculpture

No size is necessary to give this type of crystal its spectacular appearance. The visible faces, edges, and terminations are the result of its own crystalline organization. One of the most fascinating features of this specimen is that its geometry at times evokes a deliberately faceted stone, even though it results from a natural crystallization process. The large transparent surfaces are genuine observation windows. They allow the different internal levels to be followed and sometimes give the impression of observing a crystal inside the crystal.

An ancient story behind the appellation “Herkimer Diamond”

The name “Herkimer Diamond” has a long tradition in the mineral world. It historically derives from the famous double-terminated crystals discovered in the Herkimer region of New York. Their remarkable transparency, their sparkle, and their naturally highly developed geometry led collectors to visually compare them to diamonds. This designation has thus become closely associated with the spectacular aesthetics of double-terminated crystals. Crystals with comparable morphologies also exist in other deposits around the world. For this reason, the true geographic origin of the present specimen is clearly specified in its characteristics.

A spectacular piece under directional lighting

This crystal reveals its full potential when viewed under a pinpoint or directional light source. The large external faces produce clear flashes, while light simultaneously penetrates the transparent parts. It then meets the various internal structures and reflects on several levels. The result can change completely with a few degrees of tilt. Some zones appear almost perfectly clear; others suddenly become silver, shiny, or highly structured. This perpetual interaction with light makes the piece particularly interesting for display.

An exceptional subject for macro photography

The internal richness of the specimen also makes it an excellent subject for mineralogical macro photography. At high magnification, details become dramatically more impressive: tiny structures transform into reliefs, internal planes become mirrors, and the different depths take on an almost abstract dimension. A single stone can thus yield radically different photographs depending on orientation and lighting. For the collector who values both mineralogy and detailed observation of crystals, this feature is a true asset.

A singular collectible piece

With 5.20 carats, highly balanced dimensions of 11.8 × 11.8 × 6 mm, natural double-terminated morphology, beautiful transparency, and above all its particularly rich internal architecture, this specimen possesses an immediately recognizable identity.

It combines two qualities highly sought after in collectible crystals: sufficient clarity to observe deeply into its interior, yet enough complexity to offer a multitude of details to explore.

A remarkable natural mineral piece, at once geometric, luminous, and deeply complex, whose every orientation reveals a new aspect of its crystalline history.

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