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Rhombohedral dolomite crystal from this classic Navarra locality. It is disposed very aerial on a dolomite matrix. Three of the faces of the rhombohedron are dotted with small globules of goethite. A very aesthetic miniature.
Aggregates of tabular siderite crystals, with greenish tones, which are disposed on a matrix with small crystals of quartz, galena and baryte. The sample comes from this classic Almeria mine where it is not easy to find specimens of siderite with this quality. From the Aleydis Soliveres collection.
Specimen formed by a druse of quartz microcrystals on which several groups of cubic fluorite crystals have grown. They have faces that are asymmetrically beveled by the dodecahedron. Its transparency allows us to see a curious geometric zoning of color. The specimen comes from the J. Vilalta collection and the A. Soliveres collection. From a mine from which it is difficult to find pieces.
Group of neptunite crystals, well developed and rich in faces, bright and arranged on a matrix with white natrolite. The contrast is very aesthetic. It belongs from the Nicolau collection (Barcelona). The formula of neptunite indicates its chemical complexity: KNa₂Li(Fe²⁺)₂Ti₂[Si₄O₁₂]₂
A novelty from Sainte-Marie-aux-Mines 2022. These specimens come from a recent find in this mining area of the Black Forest and are reminiscent of those found decades ago in this area. They show radial aggregates of extremely brilliant pyrolusite crystals that partially replace manganite. By X-ray diffraction we have been determined the presence of both species, even with a certain predominance of manganite. They usually appear on a matrix of pink granite or as groups of large crystals in parallel growth. In the specimens we can observe the inclined flattened terminal faces. They are highly aesthetic pieces those will become part of the best specimens of these species for European mineralogy. We will send the XRD to the buyer.
This is a rich and a huge size specimen of one of the most unique species in all the mineral kingdom. Cylindrite is a lead, iron, tin, antimony sulfosalt that forms in "cylinder" or "tube" shaped crystals, hence the name. In fact, this species belongs to the only group of minerals that naturally forms rounded, curved or tubular shaped crystals. This specimen is especially nice considering that it is loaded with crystals. The mine at Poopo is the type locality for the species. A museum specimen.
Amazing aggregate of prismatic pyromorphite crystals on a baryte matrix. Many of the crystals are doubly terminated and have a good size. They shows slightly curved faces and edges, are a very brilliant olive-green color on the prism with intense yellow tips. On a baryte matrix with galena (not in quartz as the label indicates). This shape is highly appreciated by collectors. This classic French specimen was purchased by a collector to Fabre Minerals.
Old specimen that shows numerous aggregates of nickelskutterudite crystals, formerly called chloantite. Bright globular aggregates stand out against the metallic matrix. It is accompanied by the handwritten label of Joan Viñals and comes from the Nicolau collection (Barcelona).
Massive specimen of dialogite, former name for rhodochrosite. This specimen is of historical interest along with the old label that accompanies it. The sites of the old mines are now largely obscured, but there are some overgrown dumps remaining in the forest.
Good-sized specimen of kermesite from this classic Slovak locality. It shows us the characteristic acicular aggregates of kermesite, with reddish reflections on a matrix with stibnite. The specimen comes from the E. Nicolau collection (Barcelona) and was acquired from Joan Viñals (Vilanova i la Geltrú).
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.
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.
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.
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.
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. In feldspar matrix. Nowadays it is difficult to get these samples.


Specimen formed by a matrix of goethite (limonite) with cavities covered by calcite crystals accompanied by small, shiny black needles of plattnerite.