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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.
An excellent old classic from the American mineralogy. Really sharp crystals of hübnerite forming groups of parallel growths, some of them isolated. Translucent, with the intense brown color and brilliance and an esthetic contrast with the snowy white matrix. Nowadays, it is very difficult to find specimens with this quality and size... From a former Austrian collection.
Thick and good size stibnite crystal from this classic Romanian mine. It presents an elongated prism, striated, with an excellent brightness. Very rich in facets in the upper terminal part, with complex bipyramidal faces. Accompanied by baryte cristals as minor matrix. Nowadays it is difficult to find specimens of this quality from this mine. It comes from a former Austrian collection.
Very thick and good size stibnite crystal from this classic Romanian mine. It presents an elongated prism, striated, with an excellent brightness. Very rich in facets in the upper terminal part, with complex bipyramidal faces. On the main crystal we observe a group of crystals of the same mineral, finer, that suppose a second crystallization. Nowadays it is difficult to find specimens of this quality from this mine. It comes from a former Austrian collection.
Excellent specimen from Herja mine, a world-class Romanian locality for stibnite. This piece is formed by numerous groups of divergent prismatic crystals, very brilliant and with visible terminal faces. Accompanied by small rhombohedral dolomite crystals. It belongs from a former Austrian collection.
More than an excellent specimen from Herja mine, a world-class Romanian locality for stibnite. This piece, of a very good size, is formed by several groups of thick prismatic crystals with visible terminal faces. We can observe a second generation of thin crystals. Nowadays it is difficult to find samples of this quality, for museum display cases. It belongs from a former Austrian collection.
Excellent specimen from Herja mine, a world-class Romanian locality for stibnite. This piece is formed by numerous groups of divergent prismatic crystals, very brilliant and with visible terminal faces. Photographs do not do justice to the beauty of this specimen. Nowadays it is difficult to find samples of this fine quality. It belongs from a former Austrian collection.
Very rich group of sharp chalcocite crystals, some isolated and other interpenetrated, tabular and with very clear twinned pseudohexagonal forms. Intense metallic luster, gray color. They stand out on a matrix of bright calcite and small tennantite crystals. The specimens of this locality are very rare. Novelty in Sainte-Marie-aux-Mines 2017. The Mantos Cobrizos mine is a type of "mantle" deposit. This is a small Cu deposit, located in the mining district of Los Cóndores, close to Paipote, Copiapó. So far the production has been made a small scale.
The schorl specimens from Cap de Creus are well known to Spanish mineral collectors. This specimen from the 70s of the last century shows us a striated prism and defined facets of the terminal faces, something unusual. This area of the NE of Catalonia is now a Natural Park and it is totally forbidden to extract specimens.
Very brilliant specimen formed by various cerussite crystals, with a cyclic twin, well defined and translucent. They exhibit intense yellow fluorescence under LW-UV light. They are disposed on an upholstered matrix of small crystals of the same species and, to give an aesthetic touch, a group of orange baryte crystals.
Esthetic specimen formed by groups of lepidolite mica, bright and defined, on which we observe see a brilliant topaz crystal, slightly bluish and faceted, with excellent transparency. Uncommon on matrix. With old handwritten label.
Achtaragdite is a unique, rare and poorly understood pseudomorph, from this remote Siberian locality that is the Type Locality for grossular garnet. It is a variety of the grossular-hibschite garnet series and is (technically, according to mindat) a hydrogrossular-chlorite-carbonate pseudomorph after what was formerly considered to be wadalite or some other rare hydrogarnet. The real precursor mineral for these pseudomorphs is now considered to be helvite.
Achtaragdite is a unique, rare and poorly understood pseudomorph, from this remote Siberian locality that is the Type Locality for grossular garnet. It is a variety of the grossular-hibschite garnet series and is (technically, according to mindat) a hydrogrossular-chlorite-carbonate pseudomorph after what was formerly considered to be wadalite or some other rare hydrogarnet. The real precursor mineral for these pseudomorphs is now considered to be helvite.
These specimens come from the rocky outcrops that are located near the town of Serveto. These are doleritic rocks in which epidote and these prehnites are found in. Currently it is very difficult to get samples. These specimens we offer date from the years 2005-2006. Prehnite appears as globular aggregates of prismatic crystals, sometimes more developed and visible. The light green color is very uniform. Rare locality not well represented in collections.
These specimens come from the rocky outcrops that are located near the town of Serveto. These are doleritic rocks in which epidote and these prehnites are found in. Currently it is very difficult to get samples. These specimens we offer date from the years 2005-2006. Prehnite appears as globular aggregates of prismatic crystals, sometimes more developed and visible. The light green color is very uniform. Rare locality not well represented in collections.
A very aesthetic specimen from this classic Brazilian mine. Numerous aggregates of quartz crystals, with a very elongated prism, almost acicular, with well-defined terminal faces and exceptional luster and transparence. They form divergent aggregates on a siderite matrix, visible on the back, as lenticular crystals formed by flattened rhombohedra. Very aesthetic and huge size sample for this mine.
Dalnegorsk fluorite specimens are very difficult to photograph. This is the case of this piece formed by groups of cubic crystals, transparent, colorless, defined, with the edges of the cube beveled by the dodecahedron and inclusions of very curious shapes. It is accompanied by quartz crystals dotted with green chlorite. A very curious piece ...
Excellent specimen of galena, with very good luster. It shows forms of the cube and the octahedron, twinned. It has very aesthetic skeletal and ochy growths. The mine produced specimens of this quality a few years ago and now it is increasingly difficult to find them.
Numerous groups of prismatic willemite crystals in the cavities of this matrix with galena, siderite, quartz and goethite. The crystals show hexagonal shapes truncated by pinacoidal faces, they appear isolated or forming aesthetic stars. Some of them are dotted with rhombohedral crystals, between honey-colored to greenish, of siderite. Fluorescent under short wave UV light. A good size specimen of this classic Occitan Pb-Zn mine.
These pyrite specimens from this Bulgarian mining area are very aesthetic, highlighting the complex forms and penetration twins they present. Good luster and color. They are accompanied by crystals of quartz on the matrix. It comes from a mining area known as the Septemvri mine, which includes the following deposits: Sharenka, Baram, Mogilata, Osikovo and Pechinsko.
These baryte crystals are very different from the usual ones that we can see coming from this Moroccan locality and even from other deposits famous for baryte. These are prisms of different orders, the predominant third order, truncated by the second order. We observe that a white geometric growth has formed and only affects certain faces of the rhombic prisms. This zoning is unusual for the species. The crystals are transparent and brilliant.