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Highly aesthetic botryoidal malachite aggregates completely covered by a layer of slightly greenish-blue chrysocolla. We can see the malachite, with concentric growths, in some fractures. The beauty of these specimens makes them worthy of the finest collection and display case.
These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. It shows a polished section that can allow us to observe different colour tones, between green and white. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite with minor strengite. We will send the analytical results to the buyer.
These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. It shows a polished section that can allow us to observe different colour tones, between green and white. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite with minor strengite. We will send the analytical results to the buyer.
A group of brilliant pseudohexagonal chalcocite crystals, one of which stands out for its size and definition. These specimens, considered among the finest in the world, come from the M'Passa mining area in the Republic of the Congo, near the border with the Democratic Republic of the Congo. Many of the mining operations closed in the 1980s, but new workings have yielded exceptional specimens like this one.
These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by different fragments of ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. We can see different colour tones, between green and white. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite with minor strengite. We will send the analytical results to the buyer.
These specimens from the Turó de Montcada quarry are characterized by a breccia-like appearance formed by different fragments of ampelitic slate cemented with variscite, thanks to the hydrothermal fluids that circulated between them. We can see different colour tones, between green and white. This led us to consider the possibility of an alteration of the variscite that had converted it into crandallite, but X-ray diffraction studies determined that it was dehydrated variscite. We will send the analytical results to the buyer.
Fehrite is a new species found in Almeria (Spain). Years ago (2012) we identified this species in the Les Ferreres mine (Camprodon) but unfortunatelly we didn't have enough sample to finish detrmination and structural studies. Recently we found some more samples and the characterization was carried out based on the results obtained from the application of various analytical techniques: SEM-EDS, Raman and X-ray diffraction. Les Ferreres mine is the second locality worldwide for the species. We will send all reports to the buyer. In this Catalan mine, fehrite appears as elongated elongated tabular to fibrous crystals, with a delicate bluish-green tone, and fibrous terminations. Usually, it is accompanied by devilline (blue) and brochantite (green). It is the magnesium analogue of ktenasite.
An old Spanish specimen pyromorphite formed by numerous crystals, with hexagonal prism shape and a very characteristic yellowish-green colour. The luster is very good. These specimens are difficult to see in the market. It is accompanied by a handwritten label in German.
A very aesthetic and classic specimen of the hard to find and attractive chalcopyrites from the Friedrich-Wilhelm Mine. This specimen shows a brilliant, metallic, semi-iridescent, brass colored crystals of chalcopyrite scattered on the underlying quartz matrix. Richly faceted, with complex forms on the chalcopyrites. Very old material. From the former J. Vilaseca collection (Barcelona).
A fine specimen of cinnabar from the classic Spanish mine, Escarlati, in León. This specimen shows various aggregates of interpenetrating mercury sulfide crystals, with good color and visible octahedral shapes. They are arranged on a porous matrix that had been covered with calcite but was removed chemically. Only in this way can we enjoy these crystals. It comes from the Jaime Murria collection (Barcelona).
In this specimen, we can observe several hexagonal pyrrhotite crystals that have been completely replaced by pyrite. The luster is very good, and they stand out in a matrix formed by numerous quartz crystals. With black sphalerite. A very interesting and aesthetic pseudomorphosis.
The anatase crystals from this Norwegian locality are a classic of world mineralogy. They are notable for their size. In this specimen, we see a crystal formed by a tetragonal bipyramid truncated at the vertices by pinacoids. Growth contacts and some small chips can be observed, but they do not detract from the quality of the specimen. It is disopsed very aerial on a small quartz matrix.
Group of andradite crystals, which show us very well defined faces of the dodecahedron truncated at the edges by those of the trapezohedron. It has an intense brown color and a more marked shine on the trapezohedron faces. Specimen from this classic Russian town that is rare today.
The Yinnietharra dravite crystals are a classic of world mineralogy. Nowadays they are not common and can only be obtained from old collections that were lucky enough to be formed when the mines were worked. This specimen shows us a good group of doubly terminated dravite crystals, with very defined faces and edges, shiny and with the characteristic toasted honey color. They are accompanied by muscovite. An AMAZING specimen!!!
These selenite gypsum specimens show the "swallow tail" and reverse twinning. They show a certain transparence, which allows us to see the inclusions, and a good brilliance due to the natural polishing of the gypsum. The most interesting thing, in my opinion, is this rounded appearance due to the erosive action of the sea spray, since they appear in the clays of the Eocene cliffs. A very English curiosity from Jaime Murria's collection.
Specimen of fluorapatite from the famous Cerro de Mercado mine in Mexico. The main crystal is prismatic, terminating in the faces of the hexagonal dipyramid. The luster and transparency are excellent and the color is very intense greenish yellow. It is arranged on a calcite matrix containing elongated augite crystals.
Specimen of fluorapatite from the famous Cerro de Mercado mine in Mexico. It is presented as a prismatic crystal terminated by the faces of hexagonal dipyramids. The transparency and brilliance are excellent and the color is very intense yellow. It is arranged on a matrix containing hematite and small augite crystals.