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Stibiconite species totally replacing a stibnite crystal, very elongated, with multiple terminations and partially covered by scalenohedral calcite crystals with staggered growths. A classic of Mexican mineralogy. It belongs to the former Joan Astor collection (Barcelona) with a handwritten and typewritten label.
Pyrite specimens from the Elba Island are an Italian classic. But specimens of pyrite, richly faceted, sharp and brilliant included in serpentine are very rare. Undammaged. The label of this specimen indicates that it comes from this famous island. It belongs to the Joan Astor collection (Barcelona), with a handwritten and typewritten label.
This specimen of goethite after pyrite from Pedrera Berta (El Papiol, Barcelona) shows several cubic crystals completely transformed into goethite and limonite. Very brilliant and with fluorite on matrix. A classic of this mine, nowadays not easy to find. It belongs to the Joan Astor collection (Barcelona), with a handwritten and typewritten label.
In this specimen we can observe cookeite in pink tones. It is associated with eucryptite, a rare lithium aluminosilicate, and quartz. Eucriptite-quartz pseudomorphs were first discovered at this Australian mine in 1963, they are pale pink and, more rarely, dark glassy brown in color, and fluoresce reddish under shortwave ultraviolet light. Eucryptite is in the area indicated by the arrow.
The fossil woods of the US state of Washington have been well known since the 19th century. This specimen is a wood opal from this area and clearly shows the growth rings of the tree in question. If it is a fir tree or another member of the pine trees, it is already a subject on which we cannot pronounce ourselves.
As we can read in a brochure from the 80s (visit link): "Petrified wood is found throughout the state and is symbolic of our early forests. It represents a period of geological time when extensive volcanism buried great forests with volcanic ash and basaltic lava".
The uvarovite specimens from the Jeffrey are not at all common. This specimen from the Joan Astor collection (Barcelona, Catalunya) dates from the 70s, when some specimens were collected. Small but brilliant and transparent crystals of this garnet, extreme with chromium of the grosularia-uvarovite series.
A very ancient specimen showing a quartz matrix with carbonates and pyrite crystals. Covered with thin boulangerite needle-like crystals. Very brilliant and dotted with calcite or dolomite colourless rombohedrons. The original handwritten label of the Astor collection, dated in 1978, indicates it comes from Concepción del Oro, but we believe we can say it is from the Mazapil area, a locality very close to Concepción. In those years, geographical themes were not so determined. Adquired in a very "old mineral shop" in Plaça Reial square, Barcelona.
Colorless, vitreous and brilliant phacolite crystals covering the volcanic rock matrix. Phacolite is a variety of chabazite, with a pseudohexagonal lenticular shape, due to the twinning of several rhombohedrons. A very nice miniature from the former Trigo collection, from Mataró (Catalonia), with its handwritten label.
On this classic matrix from Pedrera Berta (quarry), with quartz, fluorite, pyrolusite... we can observe some cavities in which some small but brilliant rhombohedral smithsonite crystals stand out, with a golden color. Viewed under magnification they are really aesthetic to take a "microphoto". They are accompanied by malachite aggregates. Collected by the well-known Catalan mineral collector Manuel Moreno "Manolo" and from the Joan Astor collection, with labels.
A very aesthetic miniature, but with an exceptional color variation. Between red, blue and green. A delicatessen from Brazil.
A very aesthetic miniature, but with an exceptional color variation. Between red, blue and green. A delicatessen from Brazil.
Groups of octaedral magnetite crystals, some in staggered growth, with an excellent luster, very well defined faces and edges. They are disposed on a matrix of microcline crystals.


Probably čechite specimens from the "Rasa de l'Alzina" open pit works could be considered between the best crystals for the species worldwide. They are brilliant, black color and show a tabular shape defined by different order orthorhombic prisms and developed pinacoidal faces. They are disposed on a fluorite matrix. This finding is close to the Maria Magdalena mine, near of the beautiful town of Ulldemolins (Tarragona, Catalonia).
SEM-EDS and EPMA analysis show that, in some cases, on the čechite crystal surface we found copper content, but inside the crystal is near to pure PbFe2+(VO4)(OH), with minor Zn(II). In most specimens from other localities the presence of manganese is important, but these specimens are Mn free.
Group of quartz crystals, of the amethyst variety, the main one is very elongated. Very transparent, with defined faces and edges, and with a delicate and uniform purple color. From the former Trigo collection, from Mataró (Catalonia), with its handwritten label.
Rich specimen of parasymplesite from this classic Mexican mine. Several divergent aggregates of prismatic to tabular parasymplesite crystals, with a light green color on the surface and a very dark green, almost black, color inside. They are disposed on a goethite matrix with cavities layered by small honey-colored arseniosiderite crystals and adamite. This specimen belongs to the Joan Astor collection (Barcelona), with a handwritten label and another typewritten.
An old piece, showing prismatic cerussite crystals, of a snowy white color and brilliance. Striated faces of the prism and disposed by the matrix. Fluorescent under LW-UV light. The specimens of this classic Catalan mine located in the Vall de Ribes, Catalan Pyrenees, are impossible to find on the mine (almost disappeared) and are only seen in collections from years ago. It belongs to the Joan Astor collection (Barcelona), with a handwritten label, collected by himself on 1978, october.
Natanite is a rare iron and tin hydroxide. It shows octahedral crystals truncated at their vertices by the faces of the cube. In this aesthetic specimen we can observe some very well defined, transparent crystals with an intense yellow color. They stand out on a matrix with brilliant rhodochrosite crystals. An exceptional sample for the species and the locality. Although the best specimens of natanite have been found in the Potosí mine, the type locality for the species is in the former Soviet Republics of Kyrgyzstan and Tajikistan.
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.
Radial aggregates of ludwigite crystals, a rare magnesium iron borate. It is accompanied by pyrite. Usually many of these specimens have been acidified, this is not the case. It belongs to the collection of Joan Astor, with a handwritten label.
From specimens like these, this very rare species was identified: panasqueiraite. Identifying it in each sample is an almost impossible task. Panasqueiraite is a monoclinic calcium-magnesium phosphate, it would be an hydroxylated analog of isokite. In Panasqueira, its type locality, it is found as massive fine-grained aggregates together with other phosphates (fluorapatite, thadeuite, wolfeite, triplite, althausite and vivianite), with topaz, quartz and sulfides (arsenopyrite, pyrrhotite, chalcopyrite and sphalerite) in veins hydrothermal. The panasqueiraíta closely resembles the thadeuíta and the wolfeíta, but with the naked eye the three species can be distinguished by their slightly different colors: thadeuite: yellow-orange; wolfeite: pink salmon; panasqueiraite: pinkish orange.
Panasqueiraite crystals are not known, but there are always exfoliation planes {010}, also for thadeuite (Caries Curto, Jordi Fabre: The Panasqueira Mines. The Mineralogical Record, January-February 2014, volume 45, number 1).
From specimens like these, this very rare species was identified: panasqueiraite. Identifying it in each sample is an almost impossible task. Panasqueiraite is a monoclinic calcium-magnesium phosphate, it would be an hydroxylated analog of isokite. In Panasqueira, its type locality, it is found as massive fine-grained aggregates together with other phosphates (fluorapatite, thadeuite, wolfeite, triplite, althausite and vivianite), with topaz, quartz and sulfides (arsenopyrite, pyrrhotite, chalcopyrite and sphalerite) in veins hydrothermal. The panasqueiraíta closely resembles the thadeuíta and the wolfeíta, but with the naked eye the three species can be distinguished by their slightly different colors: thadeuite: yellow-orange; wolfeite: pink salmon; panasqueiraite: pinkish orange.
Panasqueiraite crystals are not known, but there are always exfoliation planes {010}, also for thadeuite (Caries Curto, Jordi Fabre: The Panasqueira Mines. The Mineralogical Record, January-February 2014, volume 45, number 1).
Diopside specimens from Castellaccio are difficult to find today. They show aggregates of radiated prismatic diopside crystals with a lavender hue due to manganese content. It is the best known species found in rodingite (a metasomatic rock) from this Italian quarry. Various analyzes have shown the presence of Co (0.5% by weight in CoO) and Mn (1.5% by weight in MnO). Associated minerals include perovskite, grossular, andradite, magnetite, titanite, apatite, pyrrhotite, and calcite (Bedognè et al., 2006). With an interesting label, from the Naïf mineral dealer (Bormio), but I have not found more information about.
Bedognè, F., Montrasio, A., Sciesa, E. (2006): I minerali della medio-alta Valtellina delle Orobie e della Val Poschiavo. Aggiornamenti sulle altre località della provincia di Sondrio. Tipografia Bettini, Sondrio, 255 pp.
These Italian calcite specimens were labeled, decades ago, as vaterite, a polymorph of calcite and aragonite. Hexagonal shapes, with well-defined, flattened and interpenetrating crystals, led to this assumption. They were obtained from a excavation works that revealed a large fissure filled with gneiss blocks of various sizes cemented by crystallized calcite. This calcite appeared as milky white pseudohexagonal prismatic crystals. This specimen belongs to the Joan Astor collection (Barcelona), with a handwritten label and another typewritten.
This esthetic floater gypsum specimen shows rosette shapes on larger crystals in parallel growth. Very defined, brilliant and with a delicate pink tone still visible. These specimens were more pink when collected but over time that hue has faded. Very fluorescent, with yellow and orange tones. The label indicates that it is from Mexican Baja California, but I am sure it is from Guerrero Negro. A magnificent specimen with many years. It belongs to the collection of Joan Astor, with a handwritten label and another typewritten. It was acquired in 1976 from Bailey Minerals (Ángel Jesús Talabán García, Segovia 1942-Madrid 2007).
Karlsbad twinned orthoclase, from this classic Spanish locality for the species and twin. It belongs to the collection of Joan Astor, with a handwritten label.