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An excellent old classic from the American mineralogy. Really sharp crystals of hübnerite forming groups of parallel growths, some of them isolated. Translucent, with the intense brown color and brilliance and an esthetic contrast with the snowy white matrix. Nowadays, it is very difficult to find specimens with this quality and size... From a former Austrian collection.
Druse of fluorapophyllite-(K) crystals covering aggregates of kinoite crystals with an intense blue color. A sample from the past, belonging to the Joan Astor collection (Barcelona), with a handwritten label and typewritten box.
Green aggregates of lindgrenite, forming shiny crusts. Some corroded crystals are observed, associated with bright molybdenite. It belongs to the Joan Astor collection (Barcelona), with a handwritten label and typewritten box.
Rich group of hemimorphite crystals forming radial aggregates, with a slightly bluish hue. It is accompanied by black, zoned, tenorite globular aggregates. It belongs to the Joan Astor collection (Barcelona), with a handwritten label and typewritten box.
A very aesthetic miniature formed by various octahedral crystals of fluorite, with a violet to purple color, which contrast on the white quartz matrix. Defined, translucent and with brilliance. The Pine Canyon deposit in New Mexico has been known for more than 20 years and are prized for its fluorite crystals.
Brilliant black andradite crystals, var. melanite, on contrasting light matrix. Well defined faces and edges. Very aerial. From the former Joan Astor collection (Barcelona).
Arborescent specimen of native copper, formed by numerous sharp crystals, with excellent luster and intense color. The piece is from the Joan Astor collection and dates from the early 70s.
These specimens are very rare in this classic locality for the rutile. The matrix is formed by interpenetrating tabular kyanite crystals coated with iridescent shades of 'turgite', a term used for the mixture of goethite and hematite. What is remarkable is a group of rutile crystals, very bright and well defined. A piece with history.
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".
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.
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.
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.
Very good size crystal of benitoite, a rare barium and titanium silicate, rich in faces, highlighting those of the trigonal dypraramid, together with those of the hexagonal dypyramid and the pinacoidal faces. Intense color and translucent. It has a small dent in one edge, common in these specimens without affecting the aesthetics of the specimen. On matrix.
A rare specimen collected in an urban setting. Colorless to white radial aggregates of acicular artinite crystals on a serpentine matrix. Aesthetic, good size, excellent quality, very rich, from the classic Staten Island locality. Artinite is a rare hydrated magnesium carbonate. This piece comes from the J. Astor collection, acquired in 1980 from Bailey Minerals (Ángel Jesús Talabán García, Segovia 1942-Madrid 2007). With old labels. An USA classic nowadays not easy to find.
Calcite gemmy crystal from this classic North American locality, very transparent, bright and with a delicate yellow color. It is disposed very aerially on a matrix with galena, sphalerite, dolomite and pyrite. It is also crystallographically very interesting because of the shapes of the elongated rhombohedron, with the faces of the scalenohedron. Acquired by J. Astor from J. Montal in the mid-1970s, with labels.
A really good sized specimen in which we highlight various orange willemite crystals, the main one is doubly terminated. They are included in rhodochrosite and on a matrix with franklinite crystals. This specimen is from the Renaud Vochten collection. The intense fluorescence of willemite stands out with a yellowish-green emission under short-wave ultraviolet light. Renaud F.C. Vochten (8 December 1933 - 29 July 2012), professor of mineralogy at the State University of Antwerpen (Belgium), with a species dedicated: vochtenite [link].
This specimen is one of the well-known calcite after glauberite pseudomorphs from Arizona. This aesthetic floating specimen shows interpenetrated crystals, very well defined faces and edges and a delicate cream tone. A classic by itself.
This specimen is one of the well-known calcite after glauberite pseudomorphs from Arizona. This aesthetic floating specimen shows interpenetrated crystals, very well defined faces and edges and a delicate cream tone. A classic by itself.
This specimen is one of the well-known calcite after glauberite pseudomorphs from Arizona. This aesthetic floating specimen shows interpenetrated crystals, very well defined faces and edges and a delicate cream tone. Good size. A classic by itself.
This specimen is one of the well-known calcite after glauberite pseudomorphs from Arizona. This aesthetic floating specimen shows interpenetrated crystals, very well defined faces and edges and a delicate cream tone. Good size. A classic by itself.
An extremely glassy opal specimen, transparent to translucent, with bluish to golden tones. An excellent specimen of opal from this classic American locality. It shows some fluorescence under ultraviolet (LW) light. An old piece from the A. Trigo collection (Mataró).
Good sized fluorite crystal from this classic North American mine. It shows the cube shape with staggered growths on one edge, along with polysynthetic growths on the faces. Translucent to transparent, bright and with a violet tone that shows geometric color zoning, more intense on the edges. With a minor "matrix" of sphalerite.
Laminar rosette-shaped covellite crystals, excellent luster and with an intense violet to purple color, with an aesthetic iridescence. They are disposed on a matrix with pyrite and quartz. The covellite crystal specimens from Butte are highly appreciated by collectors and possibly the best in the world for the species, with only a few exceptions like Sardinia ones, but even those are not as sharp. The quality of this piece is simply excellent. Nowadays, specimens with this fine crystals are rarely seen.
On a sandstone matrix some yellow crusts of coconinoite formed by small tabular to micaceous crystals. This sample has been analyzed by SEM-EDS and we will send the results to the buyer.