RAREST Herkimer Diamond — 15.10 carats Exceptional clarity - NO RESERVE PRICE - Height: 18.6 mm - Width: 13.8 mm- 3.02 g - (1)

Exceptional natural Herkimer Diamond of 15.10 carats, a specimen notably imposing and spectacular, bringing together a highly expressive biterminated morphology, large transparent zones, and above all an internal architecture of extraordinary complexity.

With nearly 19 mm in length, this piece offers a remarkable volume allowing easy observation of its inner universe: a succession of crystalline planes, veils, natural fractures, apparent cavities and reflective surfaces unfold on several levels, while some areas retain beautiful clarity and act as real windows into the heart of the crystal.

Subtle smoky to brown-gold contrasts also appear in certain structures, further enhancing its relief and depth.

The whole evokes a true miniature geological construction, where every change of orientation reveals a new internal organization. Its significant size, natural geometry, and the exceptional richness of its core make it a particularly interesting piece for a demanding mineralogical collection.

These structures constitute as many witnesses to the different stages the crystal has undergone during its formation and give this specimen an absolutely unique identity.

The term “Herkimer Diamond” here designates a rare biterminated quartz specimen, sought for its natural geometry, its brilliance, and the extraordinary complexity that certain crystals can reach.

Characteristics

- Collection name: Herkimer Diamond
- Mineral nature: Natural biterminated quartz
- Origin: Pakistan
- Weight: 15.10 carats
- Dimensions: 18.6 × 13.8 × 9.5 mm
- Morphology: Natural biterminated crystal
- Color: Colorless with internal smoky to brown-gold nuances
- Transparency: Transparent to locally translucent in the most structured zones
- Luster: Intense vitreous
- Faces: Natural, broad and highly reflective
- Internal architecture: Exceptionally rich and three-dimensional
- Special features: Multiple growth planes, veils and visible internal structures
- Format: Particularly large specimen for this typology
- Interest: Mineralogical collection, crystallography, observation under magnification and macrophotography

A specimen of remarkable dimensions

With a weight of 15.10 carats and a length of 18.6 mm, this piece has a presence significantly greater than that of small biterminated crystals typically observed.
This volume is particularly interesting as it offers more space for crystal growth and, above all, makes it much easier to appreciate the internal structures.
The crystal can be observed both with the naked eye and under magnification. Even without a loupe, its extremely complex core is immediately perceptible.
Its width of 13.8 mm and thickness of 9.5 mm also give it a massive, three-dimensional morphology that is particularly appealing.

A spectacular internal architecture

The true character of this piece becomes apparent when viewing its interior.
The crystal houses an impressive amount of structures that seem organized over several depths. Shiny planes interlace with more transparent zones, crystalline reliefs and natural veils.
Some structures appear almost silvery under light.
Others display slightly smoky or brown-gold tones that contrast with the essentially colorless envelope of the specimen.
This diversity creates a real internal landscape.

A crystal that seems to enclose other crystals

Some internal zones display extremely geometric shapes.
Thanks to the transparency of the large outer faces, these structures sometimes seem to float at the center of the crystal. The visual effect can give the impression of observing several embedded crystalline generations.
This sense of depth is particularly impressive on a piece of this size.
The eye can truly travel through the crystal from its surface to its heart, sequentially discovering several levels of structures.

The memory of a complex geological history

Each crystal is the result of a growth process that occurred under particular geological conditions.
This growth can involve different stages. The physico-chemical conditions of the environment may evolve, crystal development may be disrupted and then resume, and different structures may then become permanently recorded in the material.
Crystals with such developed internal architecture are thus true natural geological archives.
Their interest does not rest solely on their aesthetics. Every veil, every plane and every structure constitutes a physical trace of phenomena that occurred during their formation.
On this specimen, this history is particularly spectacular due to the crystal’s volume and the quantity of observable structures.

The complexity of biterminated growth

Biterminated morphology is one of the emblematic characteristics of these crystals.
To naturally develop terminations at both ends, a crystal must have conditions that allow it to grow with sufficient freedom around it.
This configuration produces naturally highly geometric forms.
When this morphology is combined with a crystal of ample size, good transparency and such a developed internal architecture, the specimen takes on a completely different dimension for a collection.
Here, the substantial mass of 15.10 carats precisely allows full appreciation of this combination.

Natural windows onto the heart of the specimen

Several large faces show remarkable transparency.
They act as true natural windows through which it is possible to explore the crystal’s interior.
Depending on the orientation, the gaze passes directly through certain zones before meeting a succession of reflective planes.
A few degrees of rotation are enough to completely alter the specimen’s appearance.
A previously transparent area can become brilliant and silvery, while a dark structure can suddenly reveal golden reflections.
This permanent transformation is one of the most fascinating qualities of the piece.

A geometry entirely shaped by nature

One of the historical reasons for fascination with these crystals lies in their appearance that seems almost cut.
Their flat faces, edges and terminations can evoke the work of a gem cutter.
Yet this geometry arises from the crystal’s natural growth.
On this specimen, the contrast between the relatively orderly outer faces and the much more complex heart is particularly successful.
The exterior forms a kind of crystalline envelope around a chaotic and extraordinarily detailed inner universe.

The history of the name “Herkimer Diamond”

The designation “Herkimer Diamond” historically originates from biterminated crystals made famous by Herkimer County and neighboring regions of New York State.
Their transparency, their brilliance, and their naturally very geometric morphology earned them this historical comparison with a diamond.
They have gradually become emblematic specimens of collectible mineralogy.
Crystals with comparable aesthetics are also discovered in other regions of the world. The geographic origin is therefore essential information and must be distinguished from this historic designation, which is why the exact origin of this specimen is indicated in its characteristics.

A piece that comes to life under light

Observation under directional lighting is particularly spectacular.
Light first passes through the most transparent zones before being intercepted by the numerous internal structures. It is then reflected in different directions, producing extremely bright flashes.
Some internal surfaces become almost metallic.
Others remain transparent and allow observation of even deeper structures.
This sequence of transparency and reflection gives the crystal a real sense of movement when slowly rotated between the fingers.

A remarkable piece for macrophotography

The piece’s large size combined with the richness of its internal architecture also makes it an exceptional subject for mineralogical macrophotography.
Under magnification, its heart becomes a world in its own right.
The tiny reliefs take on the appearance of monumental formations, the crystalline planes become mirrors, and the different depths are greatly enhanced.
It is thus possible to photograph several zones of the same crystal and obtain images that almost look like they come from different specimens.

A major piece for a collection

This specimen primarily offers the advantage of combining several characteristics in one piece: significant dimensions, natural biterminated morphology, beautiful transparency windows, vitreous luster and exceptionally developed internal architecture.
Its weight of 15.10 carats gives it a remarkable presence, while its dimensions of 18.6 × 13.8 × 9.5 mm allow the appreciation of its extraordinary inner richness without immediately requiring strong magnification.
This is not a crystal whose interest fades after a first glance. On the contrary, its complexity invites examination from different angles and under different lighting to progressively discover all its structures.

A remarkable specimen for collection, imposing, luminous and deeply complex, a true natural geological capsule whose spectacular internal architecture preserves traces of a long history of crystallization.

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