Very good specimen of molybdenite from this locality in Madrid. It appears as well-defined, bright hexagonal crystals with axial growths. It is disposed very aerial on the pegmatitic rock matrix. Very difficult to see and from Joan Viñals col.

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Specimens of bavenite from Cadalso de los Vidrios are a classic of Spanish mineralogy and pieces of this beryllium and calcium aluminosilicate had not been seen for quite some time. In this good-sized specimen formed by parallel growths of microcline crystals with albite, we can observe numerous rosette-shaped aggregates of tabular bavenite crystals, well defined, brilliant, and colorless to slightly yellowish. The specimen belongs to a North American collection.

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Kyanite specimens from this border area between the towns of Montejo de la Sierra (Madrid) and El Cardoso de la Sierra (Guadalajara) have been the subject of discussion for a long time. In the area there are different deposits from which they can belong. In this specimen, the Baltasar Sánchez label is preserved, indicating the specimen from El Zahurdón, in Montejo de la Sierra. In the area we have toponyms such as Corrales de Zahurdón. Peter Seroka, to whom this piece belonged, indicates already in 1973 the presence of kyanite about 1000 m from the milestone of Km 3 of the road from Montejo to El Cardoso (Miguel Calvo's Mines and Minerals of Spain), see discussion in this link.
This specimen shows a group of kyanite crystals on a matrix with quartz, with an intense color. It is accompanied by the two mentioned labels. Very interesting...

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Very well defined microcline crystal that shows us a very clean prism finished in complex shapes among which the Baveno twin can be observed. This specimen comes from the Peter Seroka collection and belongs from the quarries in the Bustarviejo area (Madrid).

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This specimen may not stand out for its beauty but for us it stands out for its location and the origin of the specimen. It is a chalcedony with opal from the area near Vallecas, in Madrid. Fluorescent under SWUV. The sample belongs from the Bergakademie in Freiberg and due to the attached labels we can place it in the 19th century, when Vallecas was a small village. Through the other labels we can also follow its evolution in collections until a few decades ago. A piece with history, without a doubt.

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Bavenite specimens from Cadalso de los Vidrios are a classic of the Spanish mineralogy and it had been a long time since pieces of this aluminosilicate of beryllium and calcium had been seen. On a matrix with quartz, albite, and microcline, we can observe several aggregates of tabular, transparent, and very bright crystals forming aesthetic rosettes, accompanied by small crystals of pyrite and laumontite.

Bavenite specimens from Cadalso de los Vidrios are a classic of the Spanish mineralogy and it had been a long time since pieces of this aluminosilicate of beryllium and calcium had been seen. On a matrix with quartz, albite, and microcline, we can observe several aggregates of tabular, transparent, and very bright crystals forming aesthetic rosettes, accompanied by small crystals of pyrite and laumontite.

Bavenite specimens from Cadalso de los Vidrios are a classic of the Spanish mineralogy and it had been a long time since pieces of this aluminosilicate of beryllium and calcium had been seen. On a matrix with quartz, albite, and microcline, we can observe several aggregates of tabular, transparent, and very bright crystals forming aesthetic rosettes, accompanied by small crystals of pyrite and laumontite.

Very good size specimen, formed by numerous very well defined orthoclase crystals. It was in this classic locality in the community of Madrid where, around the 70s, the Daunis-Ruscalleda family, well-known mineral prospectors and collectors from Barcelona, found quite a few very aesthetic specimens of orthoclase/microcline, accompanied by Enrique Kucera. This specimen is one of these ...

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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A very aesthetic miniature. Orthoclase specimen that shows two crystals with the Karlsbad twin. An unusual piece for this classic Spanish locality. From the Joan Astor collection (Barcelona), former Joan Abella collection (Sabadell).

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Large crystals of staurolite included in micaceous schist from this classic Spanish area. The formation of metamorphic materials of the Oriental Guadarrama range, with a medium grade regional metamorphism, includes banded shales with almandine, sillimanite, distena and andalusite.

Perovskite is an very unusual species, if we add that crystals are in good condition, damage free, and that they were collected in a locality of close to Madrid, the species becomes even more interesting... In this piece highlights a group of perovskite crystals between toasted honey to yellowish tones, cube-shaped, translucent and brilliant. One of them with a good size for the locality. They are accompanied by aggregates of octahedral magnetite crystals. A rarity. Specimen has been repaired consolidating a fissure of the matrix, not afecting crystals.

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A huge size orthoclase crystal, showing defined prism and pinacoidal faces. It present a small repared edge made many years ago by the owner Sr. L. Daunis, a very perfect work. Crystal is embeded in 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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This specimen of sepiolite comes from what is considered the most important deposit of this mineral in the world.