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From a classic locality for the species is coming this thorianite cube, with pointed faces of the octahedron, intense black color and brightness. The thorianite is a thorium oxide, almost always with some uranium content, the uranothorianite variety. This specimen contains about 5-6% by weight of uranium. We will send the analysis to the buyer.
Group of bournonite prismatic crystals, with striated faces by the cyclic twin; interesting acute terminal faces, good brilliance and complete crystals. They are accompanied by bright aggregates of acicular boulangerite and sharp pyrite crystals. They are accompanied by lenticular crystals of possible magnesite or dolomite. A sample purchased by Sr. Manchion from Dr. Joan Viñals, in the 80s. A different piece from this Peruvian locality.
The label of this specimen reads "Sevilla". In the catalog of the Manchion collection it is mentioned that this piece of schorl-dravite was acquired to Dr. Joan Viñals, at the Granollers fair in 1988. For that reason, in the absence of more info, we will leave this wonderful Andalusian region as its origin. M. Calvo talks about tourmalines in pegmatites from the Los Ángeles mine, near El Castillo de las Guardas, in Seville.
Good specimen formed by various manganese oxides, with tabular crystals of pyrolusite forming brilliant rosettes, on botryoidal aggregates of romanèchite-pyrolusite. A good old piece. Acquired by Sr. Manchion in the former minerals fair held in 1985 in L'Hospitalet de Llobregat, close to Barcelona.
Rich druse of fluorite crystals. This kind of octahedral crystals show a special brilliance due to the multiple growths of small crystals on the faces of the octahedron. This fact gives them a rough surface. Translucent, with good green color and good size. The Berta quarry-mine is in the process of filling and restoration. Not oiled. An old specimen ca. 1985, from Manchion Collection.
Interesting example of goethite with a richness and very remarkable intense iridescences. From the classic mines of Riotinto; collected in 1985, accompanied by old label.
Chrysotile fibrous veins in serpentinized marble from this classic Catalan locality.
On a matrix of quartz crystals, with azurite, there are numerous fibrous aggregates of malachite crystals. Intense color, good brilliance and silky luster. A very bright piece.
The extremely glassy, transparent to translucent opal colors range from colorless to very rich orange. A really excellent, sculptural and rich bi-colored large matrix opal example from this locality. Bright neon-green fluorescence. Very old material. Matrix opal specimens of this large size are rare from this Oregon locality.
This specimen is not a "museum specimen" but for the collectors of this "territory" it has a very good memories. It is a tourmaline, sometimes dravite other schorl, of the pegmatites of the Collserola range, in the area of Tibidabo-Sant Pere Màrtir, in the city of Barcelona. It is one of those pieces that we can not do without if we like our mineralogy. With old label.
This specimen shows a very sharp celestine crystal of good size, "lanceolated", with several defined rhombohedron faces, translucent and with a visible sky blue color. It is disposed on a matrix with calcite scalenohedral crystals. Celestine crystals from this locality are very appreciated by the collectors of Spanish minerals for their color, brilliance and definition of the faces. Nowadays it is not easy to find crystals with this size and quality from this locality.
Group of sphalerite crystals with very marked parallel and polycrystalline growths, with the predominant forms of the tetrahedron, slightly curved in faces and edges, transparent to translucent and brilliant. Toasted honey color. With the light on the backside it lights up in intense orange (see photo).
Groups of tabular saléeite to metasaléeite crystal aggregates, with a characteristic greenish-yellow color, transparent to translucent, due to the loss of water. The shade is much more greenish than the autunite.
Globular groups formed by lamellar crystals of theisite, with a bluish to green color on a matrix of dolomite. It is accompanied by crusts of claraite crystals, of an intense turquoise blue. Also with azurite. Analysis results will be sent to the buyer. Claraite is a rare copper and zinc carbonate which may contain sulfur and/or arsenic. Theisite is a rare copper and zinc arsenate-antimonate that has been described for the first time in this mine in the Catalan Pyrenees. These mineral species are the second citation in Spain.
Good size... Globular groups formed by lamellar crystals of theisite, with a bluish to green color on a matrix of dolomite. It is accompanied by crusts of claraite crystals, of an intense turquoise blue. Also with azurite and manganese oxides, probably asbolane. Analysis results will be sent to the buyer.
Theisite is a rare copper and zinc arsenate-antimonate that has been described for the first time in this mine in the Catalan Pyrenees. Claraite is a rare copper and zinc carbonate which may contain sulfur and/or arsenic. These mineral species are the second citation in Spain.
Rich group of microcline crystals, amazonite variety, showing defined faces and edges and a very aerial disposition. The color is quite good and very attractive. From an old Catalan collection.
Perovskite is an very unusual species, if we add that crystals are in good condition, damage free, and that they were collected in a locality of close to Madrid, the species becomes even more interesting... In this piece highlights a group of perovskite crystals between toasted honey to yellowish tones, cube-shaped, translucent and brilliant. One of them with a good size for the locality. They are accompanied by aggregates of octahedral magnetite crystals. A rarity. Specimen has been repaired consolidating a fissure of the matrix, not afecting crystals.
Excellent cerussite cyclic twin as a star shape in which one of the crystals predominates. Very aesthetic, between transparent to translucent and with very well defined faces and edges. With a mino rocky matrix. Pictures do not do it justice, better in "person". From this classic Moroccan mines.
An excellent twin of cerussite, partially transparent, with alternating color zoning, slightly smoked. A complete piece, in very good condition for the usual of these specimens, with only a tiny chipping in the upper part and nicks in the base, from my point of view without affecting the beauty of the specimen. Very difficult to find today and really appreciated by collectors.
These are the most fine quality romanèchite specimens ever found in Spain. These botryoidal aggregates show the velvet surface formed by several small romanèchite/pyrolusite crystals (see SEM photo). These specimens has not been treated, only fresh water. Romanèchite shows in fresh fracture the classic grey color. You can observe small but brilliant crystals of pyrolusite on the stalactitic surface. Analysis will be send to the buyer.
Vladimirite specimens from Aït Ahmane are among the world's best for the species. It is a rare arsenate that forms aesthetic rosettes of tabular to fibrous crystals, very sharp and colorless. They are accompanied by white aragonite and pink talmessite. These specimens were found in the walls near the entrance of the galleries of the 53rd vein of this Moroccan mine. The SEM-EDS analysis will be sent to the buyer.
Vladimirite specimens from Aït Ahmane are among the world's best for the species. It is a rare arsenate that forms aesthetic rosettes of tabular to fibrous crystals, very sharp and colorless. They are accompanied by white aragonite. These specimens were found in the walls near the entrance of the galleries of the 53rd vein of this Moroccan mine. The SEM-EDS analysis will be sent to the buyer.
These specimens are showing a complete pseudomorph of digenite (trigonal, Cu9S5) after pyrite (cubic, FeS2). We can see that crystals preserve the original cubic shape, with slightly curved edges and faces partially covered with greenish-colored malachite. A Spanish curiosity for pseudomorph lovers.
These specimens are showing a complete pseudomorph of digenite (trigonal, Cu9S5) after pyrite (cubic, FeS2). We can see that crystals preserve the original cubic shape, with slightly curved edges and faces partially covered with greenish-colored malachite. A Spanish curiosity for pseudomorph lovers.
Very curious specimen of dolomite from this classic Navarrese locality, which shows a rich group of rhombohedral crystals, some with small negative rhombohedron faces and very sharp edges. They are partially coated with manganese oxides that give them a black and dull surface. This kind of specimens are very unusual in collections.