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Nowadays, graphite specimens from this classic Asturian locality are very difficult to be found. These specimens show contiguous columns, with greasy luster and defined hexagonal forms. The crystal habit of natural graphite in most cases is determined by its highly anisotropic, layered structure. However, anomalous habits of graphite,determined not only by its structure, but also by the peculiarities of the growth environment, are frequently encountered, and optimization of the space available when solidifying forming columns.
Nowadays, graphite specimens from this classic Asturian locality are very difficult to be found. These specimens show contiguous columns, with greasy luster and defined hexagonal forms. The crystal habit of natural graphite in most cases is determined by its highly anisotropic, layered structure. However, anomalous habits of graphite,determined not only by its structure, but also by the peculiarities of the growth environment, are frequently encountered, and optimization of the space available when solidifying forming columns.
Nowadays, graphite specimens from this classic Asturian locality are very difficult to be found. These specimens show contiguous columns, with greasy luster and defined hexagonal forms. The crystal habit of natural graphite in most cases is determined by its highly anisotropic, layered structure. However, anomalous habits of graphite,determined not only by its structure, but also by the peculiarities of the growth environment, are frequently encountered, and optimization of the space available when solidifying forming columns.
Nowadays, graphite specimens from this classic Asturian locality are very difficult to be found. These specimens show contiguous columns, with greasy luster and defined hexagonal forms. The crystal habit of natural graphite in most cases is determined by its highly anisotropic, layered structure. However, anomalous habits of graphite,determined not only by its structure, but also by the peculiarities of the growth environment, are frequently encountered, and optimization of the space available when solidifying forming columns.
These samples of heterosite come from a classic area for the Catalan mineralogy such as Cap de Creus, in Girona. They belong from a former collection and were collected, according to the owners, by the 70s of the last century. Currently, in the Cap de Creus area, it is strictly forbidden to collect absolutely anything. These samples show aggregates of brownish-black tones, with a certain brightness, with layers of violet color and embeded in a pegmatitic matrix. No acid applied.
Bareche, in his work "Els Minerals de Catalunya, Segle XX" (2005), indicated the presence in this area of several rare Mn and Fe phosphates. He indicated that the purpurite was found in a single outcrop as small masses of violet and brownish color, along with heterosite from brown to black. From these specimens, several fragments of violet tone have been analyzed. The results have indicated that iron is predominant, with a ratio Fe:Mn, 2:1, consistent with heterosite. We do not rule out that purpurite (Mn> Fe) could be present, as member of heterosite-purpurite series.
These samples of heterosite come from a classic area for the Catalan mineralogy such as Cap de Creus, in Girona. They belong from a former collection and were collected, according to the owners, by the 70s of the last century. Currently, in the Cap de Creus area, it is strictly forbidden to collect absolutely anything. These samples show aggregates of brownish-black tones, with a certain brightness, with layers of violet color and embeded in a pegmatitic matrix. No acid applied.
Bareche, in his work "Els Minerals de Catalunya, Segle XX" (2005), indicated the presence in this area of several rare Mn and Fe phosphates. He indicated that the purpurite was found in a single outcrop as small masses of violet color, along with heterosite from brown to black. From these specimens, several fragments of violet and brownish tone have been analyzed. The results have indicated that iron is predominant, with a ratio Fe:Mn, 2:1, consistent with heterosite. We do not rule out that purpurite (Mn> Fe) could be present, as member of heterosite-purpurite series.
Tetrahedrite crystals of this Asturian mine are well known and appreciated by Spanish mineral collectors. In this specimen we have several tetrahedral crystals, also tristetrahedron shape could be appreciated. Good size and partially coated by malachite. A Spanish classic.
A group of fluorite crystals those, at first glance, seem just octahedra, but if you take a look carefully you will see complex terminations. Green color and dull luster. Acompanied by small quartz crystals. A classic from the former Manchion (Barcelona) collection, collected by himself in January, 1986.
Marcassite specimens from Reocín mine are a classic of the Spanish mineralogy. This piece, of very good size (16 cm/ 6.3 in), is a worthy representative of this species. It presents numerous well-defined crystals, most of them showing the "cock's comb" twinned habit. The brightness is very remarkable. The specimen is more than 20 years old and does not present any alteration, favored by the carbonate matrix. A definitive piece for fine displays.
Gray djurleite well defined crystals (largest group 9 mm) interpenetrated, showing octahedral forms, with triangular faces. On a matrix of copper sulphides. As usual of these specimens, they may actually correspond to phases of djurleite-chalcocite. We can consider the specimens of Las Cruces mine among the best worldwide. From the former Povill collection.
Group of cubic crystals of fluorite, with transparency, color between purple to violet, with polysynthetic growths on the faces, very defined. A Spanish classic.
Specimen with many years, from the Daunis collection (Barcelona), with the handwritten label. There are several groups of sphalerite crystals, brilliant, translucent with an intense orange color when the light passes through them. They are disposed on a matrix with dolomite crystals. The sample has not been treated, so it presents some areas with small scratches, typical of the time. A great sample from this classic Spanish mine.
Rich group of microcline crystals, some of them with the Mannebach twin, well defined. Specimen belonging to the collection of Sr. Manchion, acquired at the Sant Celoni mineral show in March 1985. A piece with history.
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.
Historically the most representative fluorite specimens from mina Moscona are yellow, recently some of violet tones have been collected. This ancient specimen is one of the few that appeared in the mine with this pink to purple color, with zoning. It is a floater, formed by growths of cubic crystals with faces with polysynthetic growths, very brilliant and translucent. They are partially covered with sharp tabular barite crystals, between transparent to opaque on the outer edges. No damage, good size and fluorescent (UV-LW). A very unusual piece for this classic Spanish mine, from a former German collection.
Scolecite and aerinite specimens from this small Aragonese town are known worldwide. This specimen shows groups of acicular prismatic crystals those form globular aggregates which, when extracted, they allow us to see the radiated growths perfectly. Snowy white color and good luster. Samples of this quality and size are rare and less nowadays. With Sr. Daunis handwritten label.
Huge size gypsum twinned crystal from a classic Spanish locality. From the Manchion collection (Barcelona).
Samples of the tungsten mine of the Parrilla are very difficult to obtain today. This specimen comes from the Manchion collection and was acquired from Dr. Joan Viñals in 1991. It shows us a druse of quartz with groups of arsenopyrite crystals stand out, with very well defined faces and edges, good brightness, interpenetrated and complete. The Parrilla was a large tungsten mine, nowadays inactive. With the Manchion handwriten label.
A very rich anatase specimen from this classic Spanish locality. Crystals are showing a defined tetragonal bipyramidal form, with striated faces. Intense color of toasted honey, translucent and brilliant. On a quartz matrix. This sample is on the corresponding page in mindat and is one of the best I've seen, not easy to find. It comes from the Marí-García collection (Castelló, Spain) and we will send label to the buyer.
hese specimens are showing a complete pseudomorph of digenite (trigonal, Cu9S5) after pyrite (cubic, FeS2). We can see that crystals preserve the original cubic shape, with slightly curved edges and faces partially covered with greenish-colored malachite. A Spanish curiosity for pseudomorph lovers. We will send analysis to the buyer.
Group of smoky quartz crystals on a matrix of microcline crystals covered by albite. They present some nick but for me it is a very good and historical specimen. From a classic Catalan locality and from the Daunis collection (Barcelona).
Celestine crystals from this locality are very appreciated by the collectors of Spanish minerals for their color, brilliance and definition of faces. This specimen shows several celestine crystals of good size, acute, with well defined faces, transparent to translucent and with a visible sky blue color. They are disposed on a matrix with calcite crystals. Nowadays it is not easy to find crystals with this size and quality from this locality.
Rich groups of radiated celestine crystals, from this Spanish classic locality. This mine is also known as Rica mine. Good size and aesthetic specimen.
This piece is formed by several interpenetrated lenticular yellowish crystals of magnesite, accompanied by dolomite rhombohedrons on matrix. We especially note the rare richness of magnesite crystals in the sample. Good sized and from a classic Spanish locality.
Rich cluster of smoky quartz crystals on a matrix of microcline crystals covered by albite. They present some nick but for me it is a very good and historical specimen. From a classic Catalan locality and from the Daunis collection (Barcelona).