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.

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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.

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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.

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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.

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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).

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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.

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A huge size orthoclase crystal, showing defined prism and pinacoidal faces, with the karlsbad twin. We think it is glued on its place on the matrix, but it is not visible. Crystal is on this porphyry granite-adamellite, part of the potent dykes with large phenocrysts of potassium feldspar (orthoclase) of great perfection. A classic Spanish locality for the species.

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Group of prismatic crystals of amazonite, a variety of microcline. With defined faces of prisms and pinacoids. It has this characteristic bluish-green color. Pikes Peak is the "mecca" of the amazonites, one of several mountains formed by the erosion of the Pikes Peak batholith, famous for its myarolytic cavities with smoky quartz, amazonite, topaz, among others. It belongs to the collection of Joan Astor, with a handwritten label and another typewritten.

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Globular gyrolite aggregates, formed by radial crystals, brilliant, olive green in color. They are disposed on a matrix partially covered with quartz crystals. It belongs to the collection of Joan Astor, with a handwritten label and another typewritten.

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Aggregates of palygorskite fibers, of an intense white color, shiny. It is identified as coming from the Núria valley, in the Catalan Pyrenees, at the foot of the Puigmal mountain. A classic locality where this mineral appeared between limestone rocks. It comes from the Joan Astor collection (Barcelona), with a handwritten label and another typewritten.

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This specimen was classified as prehnite, according to the accompanying label. When in doubt, a Raman analysis was carried out. The results indicated that it was a calcite. But a calcite from the volcanic areas of Puerto Rico... It is a globular aggregate of scalenohedral crystals. An unusual curiosity to complete unusual locations in the collection. It belongs to the collection of Joan Astor, with a handwritten label and another typewritten.

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And why not? A very brilliant piece of talc from this classic Catalan mine. In the surroundings of the locality of La Vajol there are a series of talc mines that were exploited until 1994. One of the curiosities of these talc mines, close to the France border, is that they were the hiding place, for a time, of the treasure of the Spanish Republic on the route of the main leaders of the Spanish Republic and the Generalitat de Catalunya to exile in 1939, at the end of the Spanish Civil War. It belongs to the collection of Joan Astor, with a handwritten label and another typewritten.

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These cobaltite specimens from the Espanola area, Ontario, are a classic of Canadian mineralogy. They show brilliant cubic cobaltite crystals on a matrix with calcite. Good size for this locatlity. Sudbury District was a very active mining area and, in past times, one of the best places in the world for cobaltite specimens. However, even then, it was not easy to find these specimens on the market. It comes from the Joan Astor collection (Barcelona), with a handwritten label and another typewritten.

Group of very brilliant wulfenite crystals with an intense orange color, with zoning. They stand out on a matrix of calcite. It comes from the Joan Astor collection (Barcelona), with a handwritten label and another typewritten.

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Druse of small prismatic brilliant olivenite crystals, olive green in color, transparent to translucent. They stand out on the quartz matrix. From this classic French mine. It belongs to the Joan Astor collection (Barcelona), with a handwritten label and another typewritten.

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Group of bustamite crystals, of good size and an intense orange-brown color, with visible faces. They are included in a matrix with calcite and galena. They present the natural brilliance, with exfoliation on some parts, this piece has not been acidified. Calcite is very active under UV light, with an intense orange emission. It is not very common to find pieces of this species and locality. It belongs to the collection of Joan Astor, with a handwritten label and another typewritten.

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Fan-shaped aggregates of epidote crystals with an intense green color and luster. They are accompanied by hyaline quartz crystals and fine olive green actinolite needles. A different specimen from this classic Moroccan locality.

Evansite specimens from Santa Creu d'Olorda are a classic of Catalan mineralogy. In this specimen we can see an amorphous mass of this aluminum phosphate with an intense green color and a vitreous luster. It is disposed on a graphite-bituminous shale matrix.

Classic specimen from this Zamora mine, rare to see today, formed by a layer of greenish-yellow segnitite crystals; under the magnifying glass we can see small crystals. It is accompanied by phillipsbornite and hinsdalite, of a more brownish to reddish tone. Good size specimen from this classic Spanish locality.

Rich group of linarite crystals, very bright, with well visible facets and a spectacular color. They upholster a cavity in the quartz matrix. From this classic locality for the species.

Group of hexagonal pr¡smatic crystals showing a good brilliance, characteristic color and very well defined faces and edges. From a classic Spanish mine.

These specimens show yellowish nodules included in a feldspar matrix. First SEM-EDS analysis have yielded a phosphate of Th and Ca, with minor Pb. XRD has shown patterns of "bravantite", the old name for cheralite and brockite. The chemical base formula for these species are: grayite (Th,Pb,Ca)(PO4)·H2O; cheralite CaTh(PO4)2; brockite (Ca,Th,Ce)(PO4)·H2O. REE has not been found in EDS.
We could say that this yellow nodules belongs from altered monazite, formed by mixed species cheralite-grayite, with minor brockite. Accompanied in matrix by meta-autunite. We will send the full report.

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