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Gemmy and lustrous sprays of rich yellow legrandite needles, aesthetically jackstrawed in the vug, contrasting with the gossan matrix. Good color and fanshaped transparent and defined crystals.
This specimen of legrandite shows us a group of sharp crystals of this rare zinc arsenate, with an intense orange-yellow color. It is common that some crystals appears fractured, but in this sample there are several perfect prismatic crystals, undamaged, brilliant and with an incredible transparence. I personally like isolated crystals and this piece is one of them. Good size, brightness and aesthetics, very representative for the species. Accompanied by elongated smithsonite white crystals.
These mix of crystals are showing hexagonal forms and analysis reports that they are related to Ruthenium crystals, with Osmium and Iridium. It is not easy to specify that if this or that crystal is Ru or Os, usually in this nuggets both elements could be present in different percentages. We will send analysis to the buyer.
Very sharp augite crystal of good size, very rich in faces, defined and bright. Intense black color. It is an old piece from the Manchion collection and comes from the well-known volcanic region of Olot, in Catalonia, where it is strickly forbidden to collect mineral samples.
Heterogeneite specimens of Kabolela are among the most appreciated by systematic mineral collectors. This piece shows a botryoidal aggregate, of which we consider HCoO2 formula, according to the latest studies on the species. Intense black color, brilliance, waxy luster... A classic and very aesthetic definitive specimen.
Very aesthetic specimen formed by acicular globular aggregates and fan-shaped aurichalcite crystals, with an intense blue color. They are filling the cavities of the limonite matrix with a intense contrast. With an old label from this ancient natural science store located in the center of the city of Barcelona.
Very esthetic aggregates of tabular tyuyamunite crystals. Very bright, intense yellow greenish color and contrasting with the matrix. A very representative specimen for the species.
This specimen presents a good size nodule, with an internal part with septaria structure, completely covered by very brilliant and transparent green crystals of this rare iron and calcium phosphate. In this specimen we can observe some white aggregates of fluorapatite. Anapaite nodules from the Bellver de la Cerdanya area are a classic of the Catalan and European mineralogy. The materials where these nodules appear are part of the filling of a deep lake of the upper Miocene that developed in the southern part of the Cerdanya basin.
This specimen presents a good size couple of nodules, with an internal part with septaria structure, completely covered by very brilliant and transparent green crystals of this rare iron and calcium phosphate. It is not frequent find double specimens. Anapaite nodules from the Bellver de la Cerdanya area are a classic of the Catalan and European mineralogy. The materials where these nodules appear are part of the filling of a deep lake of the upper Miocene that developed in the southern part of the Cerdanya basin.
Very curious specimen of piemontite, a rare Mn aluminosilicate near to Mn epidote, accompanied by braunite, in a shale matrix. One of its parts is cutted which allows to observe perfectly both braunite and piedmontite species. These specimens from the distant Kamchatka peninsula are not commonly available to collectors.
This specimen presents a good size nodule, with an internal part with septaria structure, completely covered by very brilliant and transparent green crystals of this rare iron and calcium phosphate. In this specimen we can observe some crystals with tabular shape, of beige tone, those can correspond to messelite. Anapaite nodules from the Bellver de la Cerdanya area are a classic of the Catalan and European mineralogy. The materials where these nodules appear are part of the filling of a deep lake of the upper Miocene that developed in the southern part of the Cerdanya basin.
This specimen is an awaruite nugget, rounded by the fluvial action. The awaruite, formerly known as "josephinite" by this North American locality, is a natural alloy of iron and nickel, with compositions within the Ni3Fe-Ni2Fe range (Ni3Fe is more common). Many people mistakenly believe that "josephinites" are of meteoritic origin, but in fact the awaruite is extremely rare in metallic meteorites. The placer deposits of this area were discovered and exploited in the middle of the XIXth century. The awaruite of this deposit is usually accompanied by serpentine, andradite and orcelite: Ni5-xAs2 (x = 0.23).
Callaghanite is an very rare copper magnesium carbonate, known from only a few localities worldwide. This specimen has bright royal-blue microcrystals and hails from the Type Locality in Nevada. Good size and rich sample.
A good sized sample of graphite showing parallel aggregates of crystals. The lusters is spectacular, with that black "flywing" tone. One of the faces of the sample has some scratches we wanted to preserve and that show the piece was used for some scientific experiments. According to the owner of the piece, the sample was collected near the end of XIXth, around 1890. Confirm that Radigara is the origin is difficult, but it does belong to the Ratnapura mining district. The metallic luster, bright and pure, has a greasy feeling, as expected. This mining area is today a place famous for its gems, but we must not forget that once it was also important for native graphite. Currently obtaining these specimens is very rare, since sapphires and rubies are obviously more valuable for miners.
Very sharp almandine-spessartine crystal from Madagascar pegmatites. Rich in faces, a textbook specimen. Under the light you can see transparencies of reddish tones, in fact it is of intense red. It is disposed very aerial on the matrix with feldspar and quartz. Complete, perfect, of a considerable size... The garnets from Ialamitana, has been found to be an intermediate almandine-spessartine (Mineralogical Record, 29, p. 132). A great piece for garnet group lovers.
Good sized specimen formed by well developed prismatic crystals of stibnite, with striated faces and well defined terminations; some of these crystals show very visible curved forms. They are partially covered by calcite, of an intense orange color, together with yellowish tone stibiconite aggregates.
Stibiconite was for a long time an acknowledged species, but is now questionable, in line with the revised nomenclature of the minerals of the pyrochlore supergroup (Atencio et al. 2010).
Very well developed prismatic colorless transparent crystals of quartz showing phantom geometrical inclusions. These inclusions of pale green fuchsite crystals takes well defined forms. Crystals are free of damage. Very interesting specimen.
Rich group of trapezohedral crystals of analcime, very bright and transparent, partially covering a cavity in the volcanic rock. They are accompanied by small yellowish globules of smectite. From this classic Spanish locality.
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.
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.
Rich group of small hexagonal prismatic pyromorphite crystals with an intense green color partially covering a quartz matrix. Crystals are very sharp and color very uniform. From a Spanish locality not well represented in collections.
From a classic locality for the species is coming this thorianite cube, with pointed faces of the octahedron, intense black color and brightness. The thorianite is a thorium oxide, almost always with some uranium content, the uranothorianite variety. This specimen contains about 5-6% by weight of uranium. We will send the analysis to the buyer.
Group of bournonite prismatic crystals, with striated faces by the cyclic twin; interesting acute terminal faces, good brilliance and complete crystals. They are accompanied by bright aggregates of acicular boulangerite and sharp pyrite crystals. They are accompanied by lenticular crystals of possible magnesite or dolomite. A sample purchased by Sr. Manchion from Dr. Joan Viñals, in the 80s. A different piece from this Peruvian locality.
The label of this specimen reads "Sevilla". In the catalog of the Manchion collection it is mentioned that this piece of schorl-dravite was acquired to Dr. Joan Viñals, at the Granollers fair in 1988. For that reason, in the absence of more info, we will leave this wonderful Andalusian region as its origin. M. Calvo talks about tourmalines in pegmatites from the Los Ángeles mine, near El Castillo de las Guardas, in Seville.
Good specimen formed by various manganese oxides, with tabular crystals of pyrolusite forming brilliant rosettes, on botryoidal aggregates of romanèchite-pyrolusite. A good old piece. Acquired by Sr. Manchion in the former minerals fair held in 1985 in L'Hospitalet de Llobregat, close to Barcelona.