RAREST Herkimer Diamond — 12.30 carats Exceptional clarity - NO RESERVE PRICE - Height: 19.6 mm - Width: 13.2 mm- 2.46 g - (1)

Exceptional natural Herkimer diamond of 12.30 carats, featuring a particularly spectacular crystal configuration: two distinct crystals intergrown with each other, forming a natural, complex, and deeply three-dimensional construction.

The piece immediately stands out for this unusual architecture: the main crystal, elongated and highly geometric, appears to host a second crystal growth that integrates into its structure, creating a set with multiple terminations, facets, and changes of direction.

The substantial transparency of several areas further allows a deep observation of this construction and the many internal structures: veils, growth planes, healed fractures, small dark inclusions, and brownish-golden nuances stack at different levels.

With nearly 20 mm in length, the specimen has a remarkable presence and allows appreciation of this complexity both to the naked eye and under magnification.

The meeting of two naturally interlaced crystals, their respective geometry and the preservation of significant transparency give this piece a particularly strong mineralogical identity: no angle reads the specimen in exactly the same way.

This is a rare bi-terminal quartz specimen, remarkable here for its multiple crystallization and the natural intergrowth of two crystalline individuals.

Characteristics

- Collection name: Herkimer Diamond
- Mineral nature: Natural bi-terminal quartz
- Origin: Pakistan
- Weight: 12.30 carats
- Dimensions: 19.6 × 13.2 × 8.7 mm
- Configuration: Two crystals naturally intergrown
- Morphology: Multiple crystallization with natural terminations
- Color: Colorless, with smoky internal nuances and brownish-golden tones
- Transparency: Transparent to locally translucent
- Luster: Highly vitreous
- Faces: Natural, geometric, and highly reflective
- Internal structure: Very complex and three-dimensional
- Particularities: Growth planes, veils, natural fractures, and visible inclusions
- Interest: Collecting specimen, crystallography, observation under magnification and macrophotography

Two crystals united in a single piece

The major feature of this specimen lies in its double crystallization. It does not simply present the classic silhouette of an isolated crystal: two crystalline individuals meet and interlock to form a unique ensemble. This interaction profoundly alters the overall geometry of the piece and multiplies surfaces, angles, and play of light.

One of the crystals constitutes the main structure, while the second naturally integrates into the whole and remains clearly perceptible thanks to changes in direction of the faces and terminations.

This architecture gives the impression of a true crystalline construction in several dimensions.

A particularly complex natural growth

The simultaneous or successive formation of several crystalline individuals can produce extremely interesting interactions. During growth, crystals can meet, locally modify their development, and continue crystallizing around their contact zone. The result is a geometry far more complex than that of a perfectly isolated individual. On this piece, this history is directly perceptible: the different orientations of the faces and the meeting of the two volumes testify to a particularly dynamic natural development.

A true archive of crystallization

The interior of the specimen also preserves many witnesses of its history. Several generations of structures are visible: very transparent zones sit alongside much more complex assemblies, traversed by reflective planes, veils, and small inclusions. Some zones take on a slightly smoky or brownish tone. Others remain almost perfectly colorless. This alternation gives the crystal remarkable depth and allows observation of several successive levels through a single face.

Nearly 20 mm of crystal complexity

With a length of 19.6 mm, the specimen reaches a particularly interesting dimension for observation. Its width of 13.2 mm and thickness of 8.7 mm provide enough volume for the double crystallization to be immediately perceptible. This size also allows appreciation of the crystal interior without requiring a loupe. Under magnification, however, the piece reveals a considerable amount of additional detail and becomes a true miniature mineral landscape.

A transparency that reveals its construction

One of the main interests is the contrast between the specimen’s complexity and its many transparent zones. Several faces act as true natural windows. Through them, deeper structures within the crystal appear, sometimes giving the impression that certain elements are suspended inside the matter. This transparency mainly helps visually understand the depth of the specimen: the gaze passes through different layers before being stopped or reflected by a crystal plane.

A piece completely different depending on its orientation

A few degrees of rotation are enough to transform its appearance. From some angles, the double structure dominates the silhouette. From others, the large transparent surfaces and the terminations draw the eye. When light reaches the internal structures, they become extremely bright and can produce small silver or slightly golden flashes. The specimen thus has several visual readings and deserves to be observed from all sides.

A geometry entirely natural

The precision of certain surfaces could easily evoke a worked stone. Yet this geometry results from natural crystal growth. The faces, edges, and terminations developed according to the mineral’s crystallographic organization, while the meeting of the two individuals created this atypical silhouette. It is precisely this tension between geometric order and natural complexity that gives the piece so much character.

The history of the "Herkimer Diamond"

The name "Herkimer Diamond" is historically associated with the famous bi-terminal crystals discovered in Herkimer County and surrounding areas, in New York State. Their luster, transparency, and natural geometry earned them this comparison with diamonds very early on. Over time, these crystals have become iconic among collectors and mineral enthusiasts. Comparable bi-terminal crystallizations exist in other parts of the world as well. The true origin of a specimen should therefore always be distinguished from this historical label—the exact origin of this piece is stated in its characteristics.

A remarkable subject for macrophotography

This double crystallization also offers considerable potential under a macro lens. Increasing magnification shifts the internal structures to a different scale: veils become vast surfaces, reflective planes resemble mirrors, and inclusions become true reference points in an extremely deep crystalline landscape. It is possible to explore several different regions of the same piece and obtain radically different compositions.

A unique collecting piece

This specimen brings together several highly sought-after qualities: good dimensions, weight over 12 carats, bi-terminal morphology, significant transparency, complex internal architecture, and especially the presence of two naturally intergrown crystals. This last feature gives it a particularly strong individuality. While a classic crystal may be valued mainly for its geometric perfection or clarity, this one tells a much more complex story: that of two crystal growth events that met and evolved together to form a single mineral piece. With 12.30 carats and dimensions of 19.6 × 13.2 × 8.7 mm, it constitutes a particularly expressive specimen, as interesting for its external morphology as for exploring its internal architecture.

A remarkable collection piece, where two naturally intergrown crystals form a true miniature geological sculpture, unique in its geometry, depth, and formation history.

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