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Rich group of fan-shaped tabular erythrite crystals in parallel growth; very brilliant, of intense color and disposed very aerial on the matrix with quartz crystals. A fine specimen from Bou Azer.
Very curious specimen formed by several cubic crystals of halite, some with hoppered growth forms, bright and translucent. A very aesthetic neoformation of these "salinas" (saltworks). Although it is believed that the Romans, in the s. I AD, they already extracted salt from the area, the saltworks of Imón were built in the 10th century and have been exploited intermittently for centuries. In 2015 they returned to production with the construction of new pools of enormous dimensions.
In the eastern part of the beach of Lapari there are the known septaria of Deba. The reef may have about 15 m, but it is not distinguished from the rest of the marly formation of the black flysch of Deba beach. The first publications on the septaria of Deba date from 1958. The upper part of the site has been totally destroyed by works, and in the part of the beach, foreign and local collectors collected numerous specimens. Currently this area has been declared of special protection within the coastal biotope Deba-Zumaia so the collection of septaria is absolutely prohibited [link]. Polished section.
Aesthetic cluster of greenish andradite crystals, very well defined, bright and slightly iridescent. From Stanley Butte, Arizona, classic locality for these specimens. No damage to any of the main crystals.
Globular aggregates formed by acicular crystals of rosasite, with colours between deep green and light bluish green. Very aesthetic and disposed on a matrix of goethite. From this classic Mexican mine.
In this specimen, we observed some sulfide aggregates very characteristic of Las Cruces mine. They were partially covered with calcite and under it appear groups of very brilliant chalcocite crystals. But the most interesting part of this specimen are the small, very brilliant crystals those cover sulphides. It is an unusual species: Luzonite. Luzonite is a rare copper sulfoarsenide. I have made the relevant analysis that yields consistent results: S 35.19%, Cu 41.82%, As 22.99% (%wt). You can find more information at espiadellabo.com.
Druse of very sharp baryte crystals showing developed and striated prismatic faces, truncated by pinacoids. The crystals are translucent, and color varies between colorless to yellowish. Excellent brilliance. Similar specimens were classified, many years ago, as hokutolite (a lead-rich baryte variety) but further analysis showed that there was only a minor lead content.
Druse of very sharp baryte crystals showing developed and striated prismatic faces, truncated by pinacoids. The crystals are translucent, and color varies between colorless to yellowish. Excellent brilliance. Similar specimens were classified, many years ago, as hokutolite (a lead-rich baryte variety) but further analysis showed that there was only a minor lead content.
Druse of small quartz crystals, some doubly terminated, partially covered by white kaolinite. Peppered by several anatase crystals, with dipyramidal faces, truncated by basal pinacoid. Very sharp, translucent and with a toasted honey tone. Very aesthetic and rare in the market.
It is interesting to say that recent analysis of the reddish ashlars of the Torre Nueva (New Tower) of the Astorga cathedral indicated that these building materials were extracted from this Cantera del Moro during XVIIth and XVIIIth centuries.
Fan-shaped aggregates of excellent roweite crystals, beige orange colour, defined, good size and with quality for this species. Roweite is a rare calcium and manganese borate. They are accompanied by white hexagonal prismatic crystals of johnbaumite, up to 7 mm, excellent for the species. Johnbaumite is a very rare calcium arsenate, the arsenic analog of hydroxylapatite. In a matrix with green andradite and transparent colorless pentahydroborite. A very complete specimen, with very rare and well crystallized species.
Group of sharp isolated octahedral fluorite crystals, from translucent to transparent. They show an interesting slight apple green color. They are accompanied by small quartz crystals. On a granite matrix. This matrix is classic for modern specimens and comes from low levels of the Berta quarry.
Group of rhodochrosite crystals with a uniform pink color, with well-defined rhombohedron echeloned and scalenohedron forms. Good gemmy transparence. They are accompanied by other smaller rhodo crystals. On a solid matrix with quartz crystals with inclusions and manganese oxides.
A very aerial malachite aggregate, showing fibrous crystals, intense colour, with zoning, and good luster. On a matrix with dolomite small crystals. A very aesthetic specimen from this classic Moroccan mines.
Really good specimen from the high Swiss mountains of the Galenstock area, 3586 m., known for its smoky quartz. This good sized piece shows several of them, with excellent transparence, very uniform smoky tone, with defined faces and edges and partially covered with 'chlorite'. They are accompanied in the matrix with numerous crystals of adularia (variety of feldspar K), well defined. A piece for the display.
Aesthetic vanadinite specimen, really good for the locality. We can observe crowned prismatic crystals with color zonació and intense brightness. An interesting article on MR: Leon, M. and Liso, M.J. (1996): Vanadinite from the Gerty Mine Badajoz Spain. Mineralogical Record, 27(5), 381-384.
Radial aggregates of stibnite crystals, very brilliant and in the rocky matrix. We can see some flattened crystals. Of this old mine where today it is difficult to find pieces.
Specimen formed by small rounded crystals of smithsonite, with an intense pink color. These specimens stand out for the town and its intense color. The mine is now closed and in the process of restoration to make a part visitable.
A historical specimen of this classic mine. Various tabular baryte crystals peppered by small but brilliant and well-shaped cinnabar crystals. These specimens are very difficult to find today.
Druse of fluorite crystals, with cube shapes, translucent and of a green color. They are partially covered by small quartz crystals that show forms of corrosion. With intense fluorescence activity under LW-UV light. Very curious. From the Manchion Collection.
Rich aggregate of malachite crystals, brilliant, with an intense green color, which stand out on a matrix of blue-green chrysocolla. Very aesthetic
Excellent stalactitic coronadite specimen, analyzed by SEM-EDS, with rounded shapes, intense gray almost black. Good size. From this classic locality for Moroccan mineralogy. With yellowish goethite matrix. You can find more information about this species and locality in the Rosell Minerals blog.
Actinolite crystals are not usual with this size and definition. The specimen shows well-defined forms of the prism and monoclinic pinacoids, with the back side exfoliated. Intense green, almost black. A sample not usual for the species. It was determined that it is not an epidote, with which it could be confused, by Raman spectroscopy.
A classic old-time specimen of hydroxylherderite, well crystallized, with sharp translucent idiomorphic monoclinic crystals. Lustrous and with a greenish-yellow tone. Associated with albite and muscovite from the Golconda pegmatite in Brazil. From Manchion Collection, purchased to Dr. Joan Viñals. Previously misidentified as herderite.
A specimen of pyromorphite from this classic Spanish locality, in Córdoba. Several crystals with an intense green color, translucent and exceptional brilliance. Hexagonal crystals show barred shapes, truncated by the pinacoids. They are disposed upholstering the cavities of the matrix. A fine sample, acquired by Mr. Manchion to Joan Viñals, in 1991. Nowadays it is not easy to find samples from this mine. The pyromorphite from San Andrés Mine has been known from the first half of the XX century.
Excellent specimen of fluorapophyllite-(K) formed by several crystals, very aerial disposed and transparent, with an intense green color, and tetragonal forms of the prism and the dipyramid very visible, with parallel growths. They are disposed contrasting with a snowy white matrix of lanceolated crystals of heulandite-Ca. A gemmy specimen.