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Aesthetic group of very bright vesuvianite crystals, with striated prisms truncated by pinacoidal faces. They are disposed very aerial on the matrix with grossular. From a Spanish locality known for its skarn (skarnoid) minerals. Prospecting works has been carried out in the area to investigate the possibilities of exploiting tungsten (scheelite).
Good size heliodor crystal. With a greenish yellow color, transparent to translucent, with some faces, some rounded and others more defined. A gem with the old label of former Lloid, by Hortensia Durán y Marçal Llòria (Barcelona). Photo is not very representative of the brilliance and transparence.
Group of kyanite crystals, of gem quality, with transparency and when light passes through them they offer an exceptional color. They are accompanied on the matrix by brown staurolite crystals and paragonite (Na mica). They stand out on a clear schistose matrix. A quality European piece that is difficult to see today. Classic and aesthetic material from this famous Swiss locality from the E. Nicolau collection (Barcelona).
Dresserite is a rare barium aluminum hydroxycarbonate and is only found in the type locality: the Francon Quarry in Montreal, Canada. The quarry, now disappeared, was literally in the middle of the city, but closed permanently in 1981. This large specimen that we offer presents several small white spheres, formed by radial crystals of dresserite, associated with small honeyed crystals of weloganite, in a matrix with calcite. We can also observe hydrodresserite crystals, a more hydrated species than dresserite. Hydrodresserite forms thicker crystals, resulting in rougher spheres than dresserite.
These specimens of adamite are among the most aesthetic that this classic Mexican mine has offered us. Botryoidal aggregates of copper-bearing adamite, shiny and also forming sheaves. Under LW ultraviolet light they present an exceptional green fluorescence. Nowadays it is difficult to find specimens with this quality.
A very heavy specimen of native antimony, with an intense, metallic luster, with internal bands of possible stibnite. It is accompanied in the oxidation zone by yellowish stibiconite and valentinite. Excellent specimen for collectors of native elements. Quite rare.
Excellent specimen formed by a large group of prismatic cerussite crystals completely covered by smithsonite crystals, rhombohedral and very bright. It is a very different piece from what can be seen in this classic Moroccan locality. A display specimen.
Franklinite, Zn²⁺Fe³⁺₂O₄, crystal of very good size, with defined faces and edges, fragmented on the back. It is disposed very aerial on a calcite matrix, with other smaller franklinite crystals, along with willemite and zincite.
Good size crystal of pleonast, a variety of spinel containing Fe²⁺. It shows complex crystalline forms of the octahedron and combinations of the octahedron with the dodecahedron or, more rarely, with those of the cube. A museum size piece, very rare to get.
Orange veins of huanghoite-(Ce), very fine grained and associated with other rare earth carbonates such as sinchysite-(Ce) and Röntgenite-(Ce), along with aegirine of greenish tones. A hard to find rarity. Bayan Obo is the world's largest rare earth deposit (REE). Interestingly the fluorite content of the ores also makes it the largest fluorite deposit in the world. You have to think that the Bayan Obo deposit is 18 km long and 3 km wide, covering a total area of 48 km². The deposit is made up of three main open pit deposits.
Group of orange quintinite crystals (quintinite-2H polytype, Mg₄Al₂(OH)₁₂(CO₃)·₃H₂O) disposed on a matrix with strontianite. Very rare species belonging to the hydrotalcite supergroup.
Pirssonite crystal, a rare, sharp, buoyant sodium calcium carbonate. As usually happens, it presents whitish efflorescences on the surface. A very unusual carbonate from the type locality at Searles Lake, a large, nearly 20 km dry lake in the Mojave Desert. On its western coast is the mining community of Trona. Borax has been mined since 1873. Today sodium sulfate, sodium carbonate and sodium chloride (halite) are also produced.
Strüverite is a variety of rutile rich in tantalum and iron, with the formula (Ti,Ta,Fe)O₂, with variable proportions of niobium (Nb). When the proportion of Ta>Nb is called strüverite, but if Nb≥Ta the variety has been named ilmenorutile. The specimens from this locality in Madagascar have been mainly determined to be of the Ta-rich variety: strüverite. An interesting specimen with a very special chemistry.
Very good specimen of joaquinite-(Ce) from this classic North American mine. In the crossite matrix (obsolete name of an intermediate amphibole between the riebeckite group and the glaucophane group) we can see two crystals of joaquinite-(Ce), a rare species with the formula: NaBa₂Ce₂FeTi₂[Si₄O₁₂]₂O₂(OH,F)·H₂O. They stand out for its perfection, with an intense orange color, translucent, with defined faces and edges, and a good size for the species. Very rare on the market with this quality.
Classic and elegant specimen from Berbes, with book-shaped baryte crystals, yellowish white in color, on which various aggregates of cubic fluorite crystals stand out, very transparent and brilliant that allow us to see a violet colour zoning. On the back we can see a handwritten attached label.
Group of prismatic arfvedsonite crystals, with parallel growth, striated faces and polycrystalline terminations, very shiny and dark green, almost black in color. Accompanied by minor feldspar as a matrix.
Group of prismatic arfvedsonite crystals, with parallel growth, striated faces and polycrystalline terminations, shiny and dark green, almost black in color. They are partially covered with feldspar. A curious specimen...
Group of prismatic arfvedsonite crystals, with parallel growth, one of them very elongated, striated faces and polycrystalline terminations, shiny and dark green, almost black, on a feldspar matrix.
Group of prismatic arfvedsonite crystals, with parallel growth, striated faces and polycrystalline terminations, shiny and dark green, almost black in color. In feldspar matrix. Nowadays it is difficult to get these samples.
Group of prismatic arfvedsonite crystals, with parallel growth, striated faces and polycrystalline terminations, shiny and dark green, almost black in color. In feldspar matrix. Nowadays it is difficult to get these samples.
Pinkish aluminotaipingite-(CeCa) aggregates on matrix. They have been analyzed and the results will be sent to the buyer. Montoso is one of the areas where the "Pietra di Luserna" or "Stone of Luserna" is extracted, a leucogranitic orthogneiss characterized by a micro-"Augen" texture and a greenish gray or locally pale blue color.
Aggregate of fibrous to acicular crystals of this rare arsenic-lead sulfosal of which Lengenbach is the type locality. It is accompanied by red realgar crystals, on a saccharaoid dolomite matrix. It is accompanied by pyrite and sphalerite. Several labels show the pedigree of the piece, with a date of 1988.
Very interesting interstitial lead laminar growth, the matrix is epidotite, a relatively uncommon metamorphic rock, formed almost exclusively of crystalline epidote. The sample is from a Swedish locality, classic for native Lead but that must not be confused with better known Långban.
Although it is not an aesthetic specimen in the conventional sense, this metacinnabar is a very interesting for the locality and unusual piece for sale. It comes from the Pietrineri mine, a mercury mine included in the famous mercury mineral complex of Monte Amiata, currently completely abandoned. Mining operations at Pietrineri began in 1902 and ceased in 1979. In the specimen we can see the vermilion of cinnabar along with black aggregates of metacinnabar.
Clinohumite specimens from the Sierra de Mijas are a classic of Spanish mineralogy. These specimens are treated using chemical processes to make the crystals emerge in the marble matrix. They are accompanied by dark violet octahedral crystals of spinel. Clinohumite is a member of the humite group. It forms a continuous series with hydroxyclinohumite. The name "clinohumite" has commonly been used when the F/OH ratio has not been determined. Mijas is a magnesium skarn embedded in marble and pelitic gneiss, amphibolites and granulitic gneiss, in the contact zone with alpine peridotites-serpentinites (Sierra de Mijas).