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Contrasting sparkly dolomite matrix are lustrous, dark green spheres to 1 mm across, of conichalcite. This is an uncommon, calcium, copper arsenate and it is rare in the form of such isolated crystals or crystal aggregates as you see here (forming little ball-shaped growths).This aesthetic specimen is double sided.
Very elongated quartz crystal with a very uniform and aesthetic smoky tone. Defined faces and edges and good transparence.
A defined fluorite cubic aggregate, echeloned growths with absolutely striking green and purple phantoms inside the otherwise glassy crystals. Cubes are lustrous on all sides and free of any considerable damage. The interior is quite fascinating as is characteristic for the Okorusu Mine. This cluster of fluorite is very aesthetic and typical for the locale.
This specimen shows us a rich group of prismatic schorl crystals, with well defined terminal faces and striated prism. Intense black color and excellent brilliance. They are accompanied by albite and muscovite crystals.
An old specimen of smithsonite, with an orange to pink hue, formed by numerous highly faceted crystals, with curved edges and disposed on a matrix with galena, iridescent chalcopyrite and other sulfides. A good sized classic...
In a vug of the matrix there are numerous complete and brilliant dioptase crystals with the characteristic intense green color. They are accompanied by small yellow crystals of duftite, on calcite rhombohedra. A very aesthetic classic from this mine.
A good size crystal of columbite-(Mn) that shows parallel growths on the faces, with striations, intense luster and black color. The accompanying handwritten label indicates that it belongs from the Etiro pegmatites, in Namíbia, a locality of which few specimens have been seen in the market. The piece belongss from H.G. Hoppert. Sample has been analyzed and the results, as can be seen in the attached documents, indicate it contains more Mn than Fe, a columbite, but with values of Nb-Ta in the border area with tantalite domain. All results will be sent to the buyer.
Old specimen of a good size formed by a matrix partially covered by small but brilliant crystals of duftite, a lead and copper arsenate, with a deep green color. They are accompanied by prismatic crystals of mimetite, between white and yellowish, together with crystals of cerussite. An entertainment under the magnifying glass. It comes from the Joan Astor collection (Barcelona), with a handwritten label and typewritten box.
These specimens show yellowish nodules included in a feldspar matrix. First SEM-EDS analysis have yielded a phosphate of Th and Ca, with minor Pb. XRD has shown patterns of "bravantite", the old name for cheralite and brockite. The chemical base formula for these species are: grayite (Th,Pb,Ca)(PO4)·H2O; cheralite CaTh(PO4)2; brockite (Ca,Th,Ce)(PO4)·H2O. REE has not been found in EDS.
We could say that this yellow nodules belongs from altered monazite, formed by mixed species cheralite-grayite, with minor brockite. Accompanied in matrix by meta-autunite. We will send the full report.
Makatite is a very rare sodium silicate. In this excellent specimen, it presents a good size aggregate formed by fine fibrous makatite needles, shiny and soft to the touch, on the matrix. It is accompanied by small but very transparent crystals of a pinkish to reddish villiaumite (NaF). Very representative for the species and the locality. Analyzed.
Globular aggregates of malachite, with an intense green color, brilliant and that stand out on a matrix of calcite. A specimen from Tsumeb and belonging from the Manchion collection (Barcelona).
Gemmy, transparent to translucent, colorless crystals of anglesite. It shows a parallel growth of dipyramidal anglesite crystals, so rare from Tsumeb! On a matrix with dark gray to black mineral, possibly one of the manganese oxides. Very unusual. It was acquired to Bailey Minerals (Ángel Jesús Talabán García, Segovia 1942-Madrid 2007).
Superb cerussite specimen from this worldwide classic locality. It shows a cyclic twin, with some more developed crystals, very brilliant, between translucent to transparent, with a very aesthetic pinkish red tone. It presents a second generation of prismatic type cerussite crystals that have grown locally on some faces. Very aerial and with a small matrix. It was acquired in 1975 from Bailey Minerals (Ángel Jesús Talabán García, Segovia 1942-Madrid 2007). A very aesthetic and good size piece.
Rich group of azurite crystals, with well-defined crystallographic forms, some of them doubly terminated. Intense and characteristic blue color and very brilliant. They are disposed on a matrix accompanied by well defined cerussite crystals, between translucent to transparent, with duftite. From this classic African mines.
Group of tarnowizite crystals, well defined, some of them interpenetrated. Milky tone and translucent. On a rocky matrix. From this classic locality and from the former Manchion (Barcelona) collection.
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.
Aesthetic group of several descloizite crystals. Every one of these group of crystals is a group of little crystals of slightly curved edges, a typical shape in the classic samples from Namibia. Intense brilliance a deep color. From this former Sapnish collection.
Incredible specimen formed by a native copper matrix, covered by calcite white rhombohedrons, very well defined and translucent. They are accompanied by numerous crystals of up to 2 mm of cuprite: exceptional under the magnifying glass. Most show the forms of the dodecahedron, but also in octahedra. A remarkable example of this classic mine.
Vuggy specimen with many cavities lined with sharp tabular wulfenite crystals. They are transparent to translucent, orange to yellow color, with green duftite throughout and malachite globular aggregates. The wulfenite crystals are coated on a druse of white calcite rhombohedral crystals. The crystals are undamaged. Very different than usual.
An interesting and showy Tsumeb specimen, puffball of lustrous primary malachite acicular crystals, nicely disposed on matrix covered with very glassy, colorless, calcite rhombohedral crystals.
Aesthetic tarbuttite specimen formed by numerous tabular crystals, forming parallel aggregates of green apple color. These tarbuttite crystals from the Skorpion mine can be considered among the best in the world. They are partially covered with tiny crystals of fluorapatite, rich in Zn, but without becoming skorpionite. To my understanding many specimens of this deposit labeled as skorpionite are scholzite and/or fluorapatite rich in Zn. We will send analysis to the buyer. It is accompanied by lanceolate crystals of hemimorphite. Good sized specimen.
A specimen from this classic locality of the world mineralogy totally different from the seen. It is an old piece of a German collection, made up of an array full of green mottramite nodules. One of its faces has been cut allowing to observe the aesthetic aggregates of intense green tone that remember leaves. He analyzed the sample and shows the presence of a certain percentage of As.The results are sent to the buyer. Something very different from Tsumeb ...
Excellent growth of cyclic twins of cerussite, with very sharp crystals and well defined faces and edges, transparent to translucent, really brilliant... A very good classic with a notable quality and coming from past 60's of the XXth. Not easy to find nowadays.