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Rich group of prismatic crystals of gaudefroyite, a rare calcium and manganese borate-carbonate, with an intense black color. They are accompanied by brilliant hematite crystals, along with barite, calcite and orange andradite.
A sharp crystal of lazurite, sitting right up on the marble matrix. A representative miniature for this species. Lazurite is the blue component of the 'gemstone' (or, more usually, decorative rock) Lapis Lazuli, which is a lazurite-calcite-pyrite rock that has been mined as a gem material for some 9,000 years. Before the 2021 redefinition, all lazurites were only sulfide-rich varieties of haüyne and not a separate species.
This specimen is totally different from those that we usually see in the market of this Moroccan locality. The matrix is a group of quartz crystals, with a soft amethyst tone, and partially covered with chalcedony, in tiny, shiny crystals. On this matrix there is a large group of goethite crystals, lanceolate, dark brown in color and also covered with chalcedony. But millimeter quartz crystals stand out above them, most of them doubly terminated. I had never seen specimens that looked like this. Very interesting.
A great sample of arsenopyrite, pale gold to silver in colour with slight iridenscence and a bright metallic lustre, with several intergrown crystals all showing complex striations and serated crystal edges. Accompanied by black ferberite. Good sized and fine specimen.
Group of tabular crystals of calcite of hexagonal shape, with color zoning and small recrystallizations of the same calcite in some areas of the piece. Crystals are on a matrix with fluorite, quartz and small pyrite crystals. It shows a intense reddish tone under UV light. Aesthetic specimen from this classic Moroccan locality.
A very attractive large specimen of beautiful "star" muscovite mica from Linópolis. These specimens are some of the most distinctive and eye-catching pieces of mica from any locality for their wonderful morphology. This piece has a full coverage of lovely golden-yellow color, incredibly well-formed, star shaped twinned crystals of muscovite on quartz matrix.
This specimen presents a good-sized anatase crystal and belongs from this unusual locality in Cáceres. It shows very defined tetragonal dipyramid shapes, with striated faces. Intense toasted honey color, translucent to opaque and shiny. It is accompanied by quartz crystals, on matrix.
Without a doubt these are the best specimens of romanechite that have ever been found in Spain. These are botryoidal romanechite aggregates, shiny and very aesthetic. We will send the analysis to the buyer.
Aesthetic group of topaz crystals aesthetically disposed on a rhyolite matrix. Some of them isolated and very rich in faces. They show very well defined faces and edges, with an excellent transparency and a uniform tone. From a classic locality.
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.
Highly lustrous, rounded faces, jet-black spinel octahedrons included in a calcite matrix from this less well-known locality. Crystals of this size and quality are rare from here and this is a fine and good sized specimen from the E. Nicolau (Barcelona) Collection.
Interesting specimen due to the town where it comes from. It is a druse (both sides) of small, brilliant jarosite crystals from this small ballast quarry for railway tracks, located in the area known as "La Corraliza" to the NNE of the town of Vall d'Uixó. With old label from J. Viñals.
This specimen belongs from a very rare location from an active quarry in Northern Ireland. It consists of a druse of white analcime with minor amounts of basalt as a matrix. Very unusual in the market. With an old label from Mikon.
Globular aggregates of prismatic baryte crystals, bright, defined, translucent and with a whitish color. A classic of Murcian mining.
Group of gypsum crystals, in parallel growth, with siderite inclusions. Open pit exploitation (corta) located next to the San Valentín corta. It belongs from the collection of Joan Astor.
In this specimen we can observe several cubic galena crystals, very brilliant and defined, with faces of the cube truncated by the octahedron. They are accompanied by complex sphalerite spinel twin crystals. Disposed on a matrix with quartz and lenticular calcite crystals.
Scalenohedral rhodo crystals with a whitish patina. They are accompanied by very brilliant hyaline quartz crystals.
Group of cubic fluorite crystals, with transparence that allows us to see the inner violet geometric zoning. Polysynthetic growths on faces. In matrix with baryte.
n this specimen of chalcedony we can observe, when light passes through it, the presence of a cavity partially filled with water of crystallization. This water was trapped in the process of formation of the geode, millions of years ago. A mineralogical curiosity.
Este ejemplar de fluorita de la cantera Berta nos muestra grupos de cristales pero también cristales aislados. La matriz es la granodiorita de color rojo "antigua" y se halla tapizada por diminutos octaedros de fluorita casi incoloros. Si algo hay que destacar de esta pieza es que los cristales octaédricos de fluorita muestran en los vértices las caras del rombododecaedro, del cubo y del tetraquishexaedro.
This specimen of fluorite from the Berta quarry shows us a group of crystals but also isolated crystals. The matrix is "old" red granodiorite and is lined by tiny, almost colorless fluorite octahedrons.
Radial aggregates of needle like erythrite crystals. They stand out from the goethite matrix.
Radial aggregates of needle like erythrite crystals. They stand out from the goethite matrix.
Radial aggregates of needle like erythrite crystals. They stand out from the goethite matrix.
Espécimen muy rico formado por numerosos agregados de cristales aciculares blancos (transparentes) de picrofarmacolita, acompañados de eritrita rosada rica en Mg (hörnesita), junto con farmacolita y sainfeldita. En matriz. Estos ejemplares fueron extraídos de la mina Bou Azer en febrero de 2018. Son muy estéticos bajo aumento, con buen tamaño para colección.