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Rich group of small pyromorphite crystals, prismatic, hexagonal and truncated by pinacoidal faces. Good color and shine. Examples of this mine are not easy to come by today. The sample is accompanied by the handwritten label of Joan Viñals.
Monazite-(Ce) crystal, floater, rich in faces, with luster and intense brown color. Nowadays finding specimens with this quality is not easy.
These specimens have been analyzed, indicating that cerium is predominant, and that it is accompanied by other REEs such as lanthanum and neodymium, together with thorium, which gives it some radioactivity. We will send the results and label to the buyer.
Very good monazite-(Ce) crystal, floater, rich in faces, with luster and light brown color. It is accompanied by a cubic crystal of columbite-tantalite embeded in. These specimens have been analyzed, indicating that cerium is predominant, and that it is accompanied by other REEs such as lanthanum and neodymium, together with thorium, which gives it some radioactivity. We will send the results and label to the buyer.
Excellent monazite-(Ce) crystal, totally floater, rich in faces, with luster and intense brown color. Nowadays finding specimens with this quality is not easy.
These specimens have been analyzed, indicating that cerium is predominant, and that it is accompanied by other REEs such as lanthanum and neodymium, together with thorium, which gives it some radioactivity. We will send the results and label to the buyer.
Group of strontianite crystals disposed on the rocky matrix. Joan Viñals's label indicates Bédar bridge, which could be the zone of the mining train bridge. It is accompanied by the handwritten label.
Groups of very well defined chalcocite crystals, with hexagonal pyramidal shapes, with striated faces perpendicular to the main axis and forming aggregates. Metallic gray luster with bluish iridescences. They are disposed on a matrix with brilliant quartz microcrystals. A classic from Kazakhstan, each day scarcer.
Yellowish-green aggregates of beaverite-(Cu), accompanied by globular groups of green osarizawaite crystals. From this classic Spanish mine.
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...
This specimen shows numerous intense red-orange crystals of crocoite accented by yellow-green microcrystals of vauquelinite. The combination of intensely colorful species made this specimen very aesthetic. It show jack-straw aggregates formed by elongated chisel shaped crystals. Few samples are seen on the market. A rare, and important, display-quality German classic from J. Viñals and E. Nicolau collection.
This specimen from the Broken Hill mine has an incredibly rich coating of the lead oxyde mineral: minium. Both sides are coated with this intense, reddish-orange lead oxide. Minium is pseudomorph after cerussite crystals. Highly representative of the species and the locality. With the handwritten label from Ausrox.
Autunite specimens, which transform into meta-autunite by losing naturally water molecules, from this Portuguese mine are among the most aesthetically pleasing in the world due to their intense yellow-greenish colour, transparence, and luster. In this specimen we can observe numerous aggregates of tabular crystals, some isolated and contrasting on the stalactitic matrix. SEM-EDS analyzes have been carried out confirming the presence of Mg, but in a very small amount. Fluorescence under LW-UV light is exceptional.
If the autunite (meta-autunite) specimens from this Portuguese mine are among the most aesthetic in the world due to their intense greenish-yellow colour, transparency and brilliance, they also stand out for being sometimes accompanied by another even more interesting species: phurcalite. It is also a hydrated calcium phosphate like autunite, but with a different structure and belonging to the phosphuranylite group (autunite is part of the autunite group).
In the analysis we have carried out by SEM-EDS (photo attached) the presence of the two phosphates becomes evident: the autunite as tabular crystals, while phurcalite appears as elongated prisms with defined terminal faces, which without magnification resemble needles. Apart from the appearance of the crystals, autunite usually has an intense greenish-yellow color and phurcalite is slightly orange-yellow. Also indicate that phurcalite does not usually fluoresce, while autunite is highly fluorescent. As we have indicated, sometimes the phurcalite is associated with autunite, so the fluorescence we see is that of the autunite. We will send analytical results to the buyer.
Autunite specimens, which transform into meta-autunite by losing naturally water molecules, from this Portuguese mine are among the most aesthetically pleasing in the world due to their intense yellow-greenish colour, transparence, and luster. In this specimen we can observe numerous aggregates of tabular crystals on matrix. SEM-EDS analyzes have been carried out confirming the presence of Mg, but in a very small amount. Fluorescence under LW-UV light is exceptional.
If the autunite (meta-autunite) specimens from this Portuguese mine are among the most aesthetic in the world due to their intense greenish-yellow colour, transparency and brilliance, they also stand out for being sometimes accompanied by another even more interesting species: phurcalite. It is also a hydrated calcium phosphate like autunite, but with a different structure and belonging to the phosphuranylite group (autunite is part of the autunite group).
In the analysis we have carried out by SEM-EDS (photo attached) the presence of the two phosphates becomes evident: the autunite as tabular crystals, while phurcalite appears as elongated prisms with defined terminal faces, which without magnification resemble needles. Apart from the appearance of the crystals, autunite usually has an intense greenish-yellow color and phurcalite is slightly orange-yellow. Also indicate that phurcalite does not usually fluoresce, while autunite is highly fluorescent. As we have indicated, sometimes the phurcalite is associated with autunite, so the fluorescence we see is that of the autunite. We will send analytical results to the buyer.
Autunite specimens, which transform into meta-autunite by losing naturally water molecules, from this Portuguese mine are among the most aesthetically pleasing in the world due to their intense yellow-greenish colour, transparence, and luster. In this specimen we can observe numerous aggregates of tabular crystals, some isolated and contrasting on the quartz matrix. SEM-EDS analyzes have been carried out confirming the presence of Mg, but in a very small amount. Fluorescence under LW-UV light is exceptional.
This specimen was purchased at the Expominer fair (Barcelona) in 1985 from a dealer who brought Peruvian material. It was labeled as "enargite" from Huancavelica, a Peruvian mining region well known among mineral collectors. The specimen shows numerous crystals with a metallic luster, isolated or in groups, on a sulfide matrix (mainly pyrite). By observing them carefully and using a magnifying glass, we were able to see different crystalline forms that indicated the presence of various species. We proceeded to extract some crystals to study them.
SEM-EDS analysis indicated that elongated prismatic crystals with polysynthetic growths on the faces and hopper shapes (perimorphosis?) were a copper sulfoantimonide, with some bismuth and arsenic. This composition and its percentages correspond to chalcostibite, and the Bi would indicate the series with emplectite. Chalcostibite was confirmed by X-ray diffraction (XRD). An unusual species and less so for this Peruvian mine.
Other crystals showed prisms with faces striated and truncated by the pinacoid. Their analysis indicated that it was a copper-lead sulfoantimonide, with traces of Bi, consistent with twinned bournonite, a species also confirmed by XRD.
On the matrix we observe crystals with tetrahedron shapes, sometimes flattened. XRD indicated the presence of tetrahedrite. SEM-EDS analysis of small crystals associated with chalcostibite indicated that it could be tetrahedrite-(Zn), with possible argentotetrahedrite-(Zn). We will send labels and all the analysis reports to the buyer.
These fluorite specimens from the classic Valzergues Fluorite mine, in France, are highly prized among collectors. This specimen shows a group of cubic crystals with a beautiful golden hue inside and a violet "phantom" zoned line following the edges. The front of the specimen is undamaged, the back shows contact with the vein wall from which it was removed, as is the case with all specimens from this mine. It fluoresces under ultraviolet (LW) light.
These fluorite specimens from the classic Valzergues Fluorite mine, in France, are highly prized among collectors. This specimen shows a group of cubic crystals with a beautiful golden hue inside and a violet "phantom" zoned line following the edges. The front of the specimen is undamaged, the back shows contact with the vein wall from which it was removed, as is the case with all specimens from this mine. It fluoresces under ultraviolet (LW) light.
A good quality cubic specimen of fluorite from the classic Yellow Vein in the Fluorite Mine, Valzergues, in France. The crystal shows a beautiful golden hue in the interior with a purple "phantom" zone line that immediately transitions into a blue-green color on the exterior faces. The front side of the specimen is in great shape, but it is contacted on the back where it was removed from the pocket wall. A very interesting piece since it shows an internal green reflection due to a planar fissure and that produces this strange effect. Fluorescent under LW-UL.
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.
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.
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.
Various aggregates of quartz crystals, some doubly terminated, with transparence and brilliance, partially dotted with small reddish globules of hematite, which partially cover a matrix with bluish crystals of fluorite. These specimens that we offer were collected at the beginning of the 70s. The mines were exploited 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.