These specimens come from the type locality for kolwezite, a copper-cobalt carbonate. Most of the "kolwezite" pieces seen on the market don't have the 1:1 Cu:Co ratio required to call them that; they usually have a 2:1 Cu:Co ratio. Of all the ones I've analyzed (and there are quite a few), even the olive-green ones maintain this ratio. In this case, we can say, to be honest, they're cobalt-rich malachite specimens. Even so, the specimens are very aesthetically pleasing. If I ever find a 1:1 Cu:Co kolwezite, I'll probably find the grail...

110 €

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A very elegant specimen composed of parallel-growing, diverging, and pallid tabular crystals with a characteristic metallic gray color. It is accompanied by a tabular barite crystal. From this classic Romanian locality.

80 €

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A very aesthetic specimen of marcasite from this classic Portuguese mine. Its stability is ensured by the carbonates in the matrix. Numerous tabular, twinned, lustrous, and iridescent marcasite crystals are present. It is accompanied by well-defined arsenopyrite crystals.

A striking specimen of marcasite from a locality located on the other side of the world, in New Zealand. The piece displays numerous twinned rooster-comb crystals. It comes from a private collector from Barcelona.

Reserved

Solid cluster of intergrown nickelskutterudite (formerly called chloanthite) from the historic Schlema-Hartenstein District. Chloanthite is now regarded as an arsenic-deficient variety of nickelskutterudite or simply as a synonym for nickelskutterudite. Nowadays is very complicate find specimens of this size and quality. Complex crystals, bright, with faces... A piece highly valued by mineralogists. From the Type Locality. Only for "deep & dark collectors". It belongs from Joan Viñals and the Emili Nicolau collection (Barcelona).

Reserved

Globular aggregates of lanceolate cavansite crystals are always aesthetically pleasing, with the typical color, and standing out against the matrix covered with tabular stilbite-Ca crystals.

Howlite specimens from the type locality are not very common on the market. This one belongs from the F. Coune collection (Belgium) and was acquired around the 1970s. It is a calcium borosilicate with botryoidal forms, polished on one side in this specimen to reveal the structures. The back shows a natural fracture.

A sculptural and classic specimen of fluororichterite from the well-known Canadian locality of Wilberforce. The finest specimens of fluororichterite in the world have been collected from this area. This is a rare species of the amphibole group. In sharp contrast to the massive calcite matrix, we can see several distinct, doubly terminated crystals. The calcite exhibits a pinkish fluorescence. An excellent and striking specimen from this classic locality.

On a matrix of polymetallic sulfides, partially covered by attractive aggregates of orange realgar crystals, numerous aggregates of hutchinsonite crystals, an interesting thallium-containing sulfosalt, are arranged in sheaves. Many of these specimens are no longer seen on the market. The matrix is ​​serrated on the back.

Reserved

A very rich group of colorless and transparent hexagonal calcite prisms with flat pinacoid terminations. They have excellent luster and are arranged on a goethite matrix. A very aesthetic specimen.

Reserved

On a matrix of polymetallic sulfides, partially covered by attractive aggregates of orange realgar crystals, numerous clusters of hutchinsonite crystals, an interesting thallium-containing sulfosalt, are disposed in sheaves; very well defined and lustrous. They are accompanied by tabular baryte crystals. These specimens are no longer found on the market.

Reserved

A particularly aesthetic specimen from this important locality with thick, platy crystals with a metallic luster radiating from a central portion on matrix. This structure gives it its name, from the Greek άστρον ("astron") for "star" and φύλλον ("phyllon") for "leaf," alluding to its star-shaped spray pattern and micaceous appearance. Very good size.

Reserved

Novelty in SMAM 2025. These are globular aggregates of acute strontianite crystals, white, with a certain transparency, and standing out against a matrix of celestine crystals, very defined, rich in facets, transparent, and lustrous. They come from a mine called "Siniye Kamni" (Russian: Синие Камни), which in Russian means "blue stones," according to the Russian supplier, one of the few at SMAM. They have been analyzed using scanning electron microscopy (SEM-EDS).

Reserved

Novelty in SMAM 2025. These are globular aggregates of acute strontianite crystals, white, with a certain transparency, and standing out against a matrix of celestine crystals, very defined, rich in facets, transparent, and lustrous. They come from a mine called "Siniye Kamni" (Russian: Синие Камни), which in Russian means "blue stones," according to the Russian supplier, one of the few at SMAM. They have been analyzed using scanning electron microscopy (SEM-EDS).

Reserved

Novelty in SMAM 2025. These are globular aggregates of acute strontianite crystals, white, with a certain transparency, and standing out against a matrix of celestine crystals, very defined, rich in facets, transparent, and lustrous. They come from a mine called "Siniye Kamni" (Russian: Синие Камни), which in Russian means "blue stones," according to the Russian supplier, one of the few at SMAM. They have been analyzed using scanning electron microscopy (SEM-EDS).

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Novelty in SMAM 2025. These are globular aggregates of acute strontianite crystals, white, with a certain transparency, and standing out against a matrix of celestine crystals, very defined, rich in facets, transparent, and lustrous. They come from a mine called "Siniye Kamni" (Russian: Синие Камни), which in Russian means "blue stones," according to the Russian supplier, one of the few at SMAM. They have been analyzed using scanning electron microscopy (SEM-EDS).

Reserved

These plover specimens usually come loose, off the matrix. In this specimen, we can see a doubly terminated crystal on a sericite-talc matrix.

Idiomorphic cerussite crystals, rich in faces, lustrous, translucent, and with intense UV-LW light response. On a matrix of baryte crystals.

55 €

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The acanthite crystals from this mine located near Guanajuato, Mexico, are world-renowned. The specimens we occasionally find for sale are usually aggregates of cubic-shaped crystals. This specimen we offer stands out for its centimeter-sized, highly defined crystal, with the usual cube faces truncated by the octahedron. The metallic luster is very good and it is arranged airily on a matrix formed by small, hyaline quartz crystals. An exceptional and ancient piece...

Highly aesthetic botryoidal malachite aggregates completely covered by a layer of slightly greenish-blue chrysocolla. We can see the malachite, with concentric growths, in some fractures. The beauty of these specimens makes them worthy of the finest collection and display case.

Very aesthetic botryoidal malachite aggregates completely covered by a layer of blue chrysocolla. We can see the malachite, with concentric growths, in some fractures. The beauty of these specimens makes them worthy of the finest collection and display case.

Highly aesthetic botryoidal malachite aggregates completely covered by a layer of slightly greenish-blue chrysocolla. We can see the malachite, with concentric growths, in some fractures. The beauty of these specimens makes them worthy of the finest collection and display case.

These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. It shows a polished section that can allow us to observe different colour tones, between green and white. We can observe folds called stigmatic, produced by the entry of a viscous fluid (variscite) into a less viscous one. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite with minor strengite. We will send the analytical results to the buyer.

Reserved

These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. It shows a polished section that can allow us to observe different colour tones, between green and white. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite with minor strengite. We will send the analytical results to the buyer.

40 €

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These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. It shows a polished section that can allow us to observe different colour tones, between green and white. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite with minor strengite. We will send the analytical results to the buyer.

55 €

Buy