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Very aesthetic specimen that shows various globular and stalactitic aggregates of malachite, velvety and green color with zoning. Peppered by small malachite crystals, under the magnifying glass we can see that they are small transparent and defined crystals. In a matrix with goethite. From this classic Congolese locality for the species.
Group of quartz crystals in parallel growth and with a "scepter" structure. Very well defined faces and edges, brilliant and transparent to translucent. Very aerially disposed on the matrix. An good size and excellent specimen from a Moroccan locality not very known.
Group of complex sphalerite crystals with striated facets. Bright, translucent and with a toasted honey color. Exfoliated on the back.
Group of very elongated prismatic crystals, in parallel growth, very brilliant. The back side has a coating of quartz microcrystals. A piece from the Astor collection acquired in 1974 from Bailey Minerals (Ángel Jesús Talabán García, Segovia 1942-Madrid 2007).
In a vug of the matrix there are numerous complete and brilliant dioptase crystals with the characteristic intense green color. They are accompanied by small yellow crystals of duftite, on calcite rhombohedra. A very aesthetic classic from this mine.
Exceptional and old specimen of cerussite from this classic Moroccan locality. It presents several divergent prismatic to tabular crystals of good size, twinned in a "V" shape. Translucent and with a smoky hue. Pure aesthetics, a very difficult specimen to get nowadays.
Druse of tabular wulfenite crystals, transparent, well defined and with a soft yellowish to greenish hue. They are accompanied, on a goethite matrix, with sheaf aggregates of mimetite crystals. Very aesthetic.
Quartz specimen with marked "window" growths with inclusions. These Allos pass crystals are not very common on the market. Allos pass is situated on the edge of Mercantour National Park approximately 20 km from the small village of Barcelonnette.
Blocky aerinite criptocristalline with fragments of dolerite included. Aerinite was used as a blue pigment in many Romanesque paintings in the Pyrenees between the 11th and 14th centuries. Its characteristic blue color varies from dark to pale blue. In fact, its name comes from a Greek root aerinos meaning "atmosphere" or "sky", as it was only known by that color.
Group of cyclically twinned bournonite crystals, with a metallic gray color, interpenetrating each other. They are disposed on a matrix of very brilliant octahedral pyrite, partially covered by complex sphalerite crystals.
Group of octahedral pyrite crystals, very brilliant and well defined, which are accompanied by complex crystals of sphalerite. On them we observed numerous white globular crandallite aggregates (analyzed by XRD). This combination of minerals is unusual in the deposit, with this phosphate being the first citation.
Druse of pyrite crystals with faces of the cube and rhobododecahedron, with diploid forms, striated faces, complex crystallography, which adds interest to the specimen. The luster is exceptional, not easy to take photos. The crystals are interpenetrated. A classic from the mine from which the bases for the FIFA football award "Ballon d'Or" are obtained...
Compact mass of purple chromian iowaite with minor inclusions of greenish-brown serpentine. Iowaite is one of the former minerals on the locality and mostly replaced by stichtite, which forms a similar aggregates but is more light, lilac coloured.
Rich specimen showing wire aggregates of native silver, curved, with curls, shiny and with a very aesthetic golden tone. Some have darker areas of acanthite. They are accompanied by small but well-formed hexagonal pearceite-T2ac crystals. With calcite matriz. This piece is surprising when looking at the cavities under magnification. It berlongs from the Sarbaiskoe deposit, the best known silver producing area in Kazakhstan. Very rare to find specimens from this locality.
Good size and rich aggregate of andradite-grosularia crystals with an intense brown color on the surface, but with color zoning, clearer inside. The exterior of the sample shows a dark reddish-brown tone with very well defined trapezohedral crystals, but inside the crystals have a very aesthetic golden tone. Multi-layered bands ranging from reddish brown to green to gold are shown in the fracture zones of the piece. For this reason we prefer to label it as the andradite-grossular series.
A rich group of cube octahedral galena crystals, with ancient exfoliated zones and certain luster, but with the old patina we have preferred not to remove, since it is an old piece from the classic Príbram mining area. They are disposed on a matrix with pyrite and quartz crystals. With a handwritten label.
Rich group of complex and brilliant chalcopyrite crystals contrasting on a matrix of barite crystals. They are accompanied by interpenetred rhombohedral dolomite crystals. The specimen belongs from the Dreislar mine, a mine that was operated from 1970 to 2007, with the usual interruptions, for lead, zinc and copper, and more modernly for baryte. The specimens are classics in German collections.
Very good sized specimen of rhodochrosite from this classic Argentine locality. In the polished part we can enjoy the characteristic bands, with good color. And the "natural" part tells us that it belongs from a vein. It has a handwritten label attached on the sample and due to its appearance it was a very old piece.
Aesthetic specimen of opal with notable bluish iridescences in a very fine-grained sandstone matrix. From Quilpie area, a locality with an economy based on the grazing and mining industries. The area has one of the largest deposits of boulder opal in the world. A gem...
Very aesthetic specimen that shows two generations of orpiment. One with an intense orange color, formed by numerous brilliant crystals. A second generation formed by crystals that cover the arsenopyrite-pyrite matrix, with a darker tone. A different sample from this classic Peruvian mine.
A good size crystal of columbite-(Mn) that shows parallel growths on the faces, with striations, intense luster and black color. The accompanying handwritten label indicates that it belongs from the Etiro pegmatites, in Namíbia, a locality of which few specimens have been seen in the market. The piece belongss from H.G. Hoppert. Sample has been analyzed and the results, as can be seen in the attached documents, indicate it contains more Mn than Fe, a columbite, but with values of Nb-Ta in the border area with tantalite domain. All results will be sent to the buyer.
Floater crystal of columbite-(Fe), with a huge size for the species. We can observe numerous facets, some with striations, with brilliance. The specimen indicates "repaired" since a part (see photo) has been repositioned in its place, without affecting the quality. It is accompanied by minor lepidolite. Columbite specimens of this size are not common. We have analyzed the specimen and, in the attached diagram, we can see the results which indicate sample is in the columbite-(Fe) domain. Minor traces of Ti are present. We will send this results to the buyer. An exceptional piece.
A typical polished slice of 'Federpyrit' (variety "feather pyrite"), with a good size. This is a pseudomorphs of pyrite after thin tabular pyrrhotite. Classic specimen from Pfaffenberg, an ancient German lead-silver mine. With siderite. Very appreciated for European collectors.
A very interesting specimen of sphalerite that shows a very aesthetic cyclic twin, unusual for the species and for this classic mine. Very brlliant, with galena crystals on matrix.
Specimen of native silver from this more than classic Mexican locality such as Batopilas. This specimen shows numerous herringbone-patterned, arborescent and skeletal silver aggregates formed by crystals spinel-twin, very elegant and with luster and colour. They are disposed aerially on a matrix with calcite. Finding specimens of this quality and size (and price) from this mine is not easy at all. It belongs from a former Austrian collection.