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Aesthetic group of topaz crystals aesthetically disposed on a rhyolite matrix. Some of them isolated and very rich in faces. They show very well defined faces and edges, with an excellent transparency and a uniform tone. From a classic locality.
Highly lustrous, rounded faces, jet-black spinel octahedrons included in a calcite matrix from this less well-known locality. Crystals of this size and quality are rare from here and this is a fine and good sized specimen from the E. Nicolau (Barcelona) Collection.
Interesting specimen due to the town where it comes from. It is a druse (both sides) of small, brilliant jarosite crystals from this small ballast quarry for railway tracks, located in the area known as "La Corraliza" to the NNE of the town of Vall d'Uixó. With old label from J. Viñals.
In this specimen we can observe several cubic galena crystals, very brilliant and defined, with faces of the cube truncated by the octahedron. They are accompanied by complex sphalerite spinel twin crystals. Disposed on a matrix with quartz and lenticular calcite crystals.
Este ejemplar de fluorita de la cantera Berta nos muestra grupos de cristales pero también cristales aislados. La matriz es la granodiorita de color rojo "antigua" y se halla tapizada por diminutos octaedros de fluorita casi incoloros. Si algo hay que destacar de esta pieza es que los cristales octaédricos de fluorita muestran en los vértices las caras del rombododecaedro, del cubo y del tetraquishexaedro.
This is a specimen of tabular barite crystals, colorless to yellowish tones and very good transparence. It belongs from the Mines d'Osor, currently closed and from which it is impossible to obtain these specimens. The mine closed in 1979 and had eleven levels, with a 290 meter deep shaft. You can still see the ruins of the old facilities and the well from which sphalerite, galena and fluorite were extracted and treated.
A rich group of epidote crystals of a very good size and an intense green, almost black color. The crystals show very well defined prism faces of different orders. This crystal shape is quite unusual for this Moroccan locality.
Botryoidal aggregates of smithsonite with a very tastefull bluish green colour, translucent and with brilliance. They are disposed on matrix. From a very interesting American locality. It fluoresces intensely under LW-UV light.
Excellent specimen of fluorapophyllite-(K) with very good size crystals that show the shapes of the tetragonal prism with faces of the dipyramid truncated by the basal pinacoid. Very good transparency, brilliance and definition. It is disposed very aerial on a matrix with stilbite. With handwritten label by Joan Viñals.
Group of garnet crystals belonging to the almandine-spessartine series, usually with a predominance of the first one. The analyzes indicate the presence of Fe and Mn, with traces of Mg. These specimens were identified as pyrope (magnesium aluminosilicate), but the analytical results do not indicate this.
Group of interpenetrated pyrite crystals with an exceptional luster. This specimen stands out for its complex crystallography, with cube shapes, triglyphic striations, and vertices rich in probably trapezohedral faces. A piece to enjoy in its study, the kind that I like...


Excellent specimen of bournonite from this classic Kosovar mine. Several crystals of this lead and copper sulfoantimonide are disposed on a matrix formed by brilliant crystals of pyrite, sphalerite and galena. The bournonite presents visible cyclic twins, semi-matt luster, with chalcopyrite. They appear covered with calcite that is removed by chemical processes.


Very esthetic specimen of calcite formed by various flattened interpenetrated rhombohedral crystals, almost lenticular, with very well defined and striated faces. Between translucent to transparent, shiny and on a rocky matrix. It exhibits intense pink to red fluorescence under UV-LW light. Good size and quality.
White elongated crystals of pearly luster in parallel growths implanted on groups of crystals of malachite with a silky luster and a very deep and uniform color. From a find ca. 2010 in Bou Beker where this association had not been found before.
This is a really good crystal cluster of bismuthinite from the Mina Tazna in Bolivia. It is formed by large, terminated, prismatic crystals of bismuthinite, divergent, gray metallic. Some crystals show a metallic patina from a thin coating of marcasite/pyrite. On the back side some quartz crystals and gray-white uncovered metallic natural bismuthinite crystals. The Tazna Mine is a historic bismuth-tungsten mine in the high Andes of Bolivia that has produced noteworthy specimens for decades. Samples with this quality are very rare seen on the market. Specially for connoisseur "gray" mineral collectors...
Group of baryte crystals, between translucent and transparent, colorless and of good size, one of them standing out. They show faces of the orthorhombic prisms and the pinacoid. The largest one shows beveled edges, with an part contacted by a disapeared matrix. It is accompanied by powdery hematite. It is a sample with many years.
Fluorite specimens from Sant Marçal mines usually appear as aggregates of cubic crystals, defined, sometimes sprinkled or partially covered by quartz crystals. Yellow to greenish tones are the usual ones. Specimens with violet to bluish or green colors (depending on the type of incident light) are much less frequent and highly appreciated by collectors. These specimens we offer were collected at the beginning of the 70s. In this specimen we can observe cubic crystals with this bluish to greenish tone, translucent and disposed on a characteristic ochy "pegmatite" matrix. They are partially covered with small but brilliant quartz crystals.
The Sant Marçal mines (also known as Matagalls mines) are located in the Montseny massif, on the eastern slope of the Matagalls peak (1,700 m). Mining works were carried out at 1,250 to 1,350 m of altitude. They were mined until the mid-90s and have been partially restored. Currently this area belongs to the Montseny Natural Park, so the collection of specimens is totally prohibited.
Anglesite specimens from this classic Moroccan mine are quite difficult to find. In this piece we can see numerous lanceolated prismatic crystals of this lead sulphate, very brilliant, with well defined faces and edges, transparent and showing the natural yellow colour characteristic of this species and mine. They are disposed filling cavities in a galena matrix.