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Dadsonite is a rare chloro-sulfoantimonide of lead, compositionally differing from boulangerite by this chlorine anion (1 atom of Cl for 60 atoms of S!). In the "bad-lands" area of Sant Ponç (or Saint-Pons) there are lenticular levels of siderite and calcite. The formation of this rare sulfosalt is based on the redissolution of other sulfosalts in the presence of chlorides.
The fine needles of dadsonite usually appear included in calcite, along with boulangerite. Once the calcite is removed by chemical processes, needles emerge in all their beauty. It can also be found forming radial aggregates in matrix cavities. The dadsonite from Sant Ponç can probably be considered among the best worldwide.
This specimen shows various groups of prismatic pyromorphite crystals, with terminal faces of the dipyramid, brilliant, colourless and transparent. They stand out on a matrix of goethite with orange tone. This locality is not one of the most common for this species. This specimen from Le Kaymar can be considered among the best seen for the mine.
In this Bolivian Andean mining area, around 2010-2013, a small area with antimony and silver ore was found, highlighting some specimens of stephanite, a silver sulfoantimonide. This floater specimen is formed by a group of interpenetrated crystals, with parallel growth, and showing orthorhombic prism shapes with striations and complex terminal faces. It is distinguished from pyrargyrite by being completely opaque to light, while the latter usually gives red colors (red silvers). An exceptional specimen reminiscent of the best and ancient Mexican stephanite, although this is from the Porco mine, the oldest and most significant silver mine in Bolivia.
In this Bolivian Andean mining area, around 2010-2013, a small area with antimony and silver ore was found, highlighting some specimens of stephanite, a silver sulfoantimonide. This floater specimen is formed by a group of interpenetrated crystals, with parallel growth, and showing orthorhombic prism shapes with striations and complex terminal faces, some of them are doubly terminated. It is distinguished from pyrargyrite by being completely opaque to light, while the latter usually gives red colors (red silvers). An exceptional specimen reminiscent of the best and ancient Mexican stephanite, although this is from the Porco mine, the oldest and most significant silver mine in Bolivia.
In this Bolivian Andean mining area, around 2010-2013, a small area with antimony and silver ore was found, highlighting some specimens of stephanite, a silver sulfoantimonide. This floater specimen is formed by a group of interpenetrated crystals, with parallel growth, and showing orthorhombic prism shapes with striations and complex terminal faces. It is distinguished from pyrargyrite by being completely opaque to light, while the latter usually gives red colors (red silvers). An exceptional specimen reminiscent of the best and ancient Mexican stephanite, although this is from the Porco mine, the oldest and most significant silver mine in Bolivia.
In this Bolivian Andean mining area, around 2010-2013, a small area with antimony and silver ore was found, highlighting some specimens of stephanite, a silver sulfoantimonide. This floater specimen is formed by a group of interpenetrated crystals, with parallel growth, and showing orthorhombic prism shapes with striations and complex terminal faces, some of them are doubly terminated. It is distinguished from pyrargyrite by being completely opaque to light, while the latter usually gives red colors (red silvers). An exceptional specimen reminiscent of the best and ancient Mexican stephanite, although this is from the Porco mine, the oldest and most significant silver mine in Bolivia.
Las Cruces mine, northwest of Seville, is an example of mining in the Iberian Pyrite Belt. But it must be said that minerals those have been found there are not at all common in other deposits of this geological megastructure. Exceptional specimens of chalcocite and djurleite stand out from this mine. This specimen we offer is a magnificent specimen of the latter species, djurleite (an orthorhombic copper sulfide). We can observe aggregates formed by several idiomorphic crystals with octahedral shape and a metallic gray luster. They are disposed on a matrix formed by other copper and iron sulfides. As is usual in these specimens and has already been indicated in previous studies, these crystals may correspond to phases of djurleite/chalcocite. In this case we have carried out an X-ray diffraction that confirms it is djurleite.
Aesthetic sprays of acicular transparent natrolite crystals on vuggy basalt matrix. Very unusual specimen on the market fro this locality. Analyzed specimen SEM-EDS.
Tabular lanceolated crystals of baryte, translucent in the core and opaline in the outer areas, interpenetrated and brilliant. They are disposed on a matrix formed by small siderite crystals and layering septarian cavities. An Aragonese mineral curiosity.
Tabular lanceolated crystals of baryte, translucent in the core and opaline in the outer areas, interpenetrated and brilliant. They are disposed on a matrix formed by small siderite crystals and layering septarian cavities. An Aragonese mineral curiosity.
Group of twinned dolomite crystals of good size, peppered by numerous bright, golden cubic pyrite crystals that give the specimen a special touch. They are not common in this classic Spanish mine. The piece belongs from the collection of Andrés Jiménez Shelly (Madrid) and is accompanied by an handwritten label.
Radial aggregates of normandite, of intense orange color and with transparency. They are disposed in a matrix with aegirine/augite and analcime. Under LW-UV light the white matrix shows some fluorescence with intense orange spots. From the alkaline pegmatites of the Kola peninsula.
Twinned cinnabar, with well defined faces and edges, red color slightly silvery, well formed and almost 2 cm in size. It is disposed in a very aesthetic way on dolomite crystals. At the time, this locality produced world-class specimens such as the one we offer. Simply spectacular.
This specimen has a bit of history... The piece was acquired in May 1987 at a fair in Segovia that was held in the Lozoya tower. At that time the labels were rather "approximate". This specimen was labeled as "Poitiers" chalcedony. Looking for intertwined information between chalcedony and France, it turns out that there is a locality where similar chalcedonies appear, near Vienne, in Mauprévoir. Curiously, this locality is in a historical region named Poitou-Charentes (Peitau i Charantas in Occitan), which makes us think that the correct locality is Mauprévoir. Old and fine specimen.
Very aesthetic specimen formed by several aggregates of vanadinite crystals, labeled as arsenical endlichite. Very well defined hexagonal prisms, beige in color, peppered with tiny but brilliant and well defined crystals of descloizite-mottramite, with dark honey tones. The descloizite-mottramite forms globules but also partially covers vanadinite crystals, especially on the pinacoidal faces and forming "half moons", a curiosity. These specimens from this Moroccan mine are not common.
Smoky quartz crystals in parallel growth. Translucent, with a uniform smoky tone, they alternate glossy and matt faces. The quartz crystals from this quarry are a classic of Catalan mineralogy. Currently works are abandoned and it is difficult to find new specimens.
Smoky quartz crystal on a microcline matrix. Translucent, with a uniform smoky tone, it alternates brilliant and matte faces. The quartz crystals from this quarry are a classic of Catalan mineralogy. Currently works are abandoned and it is difficult to find new specimens.
Microcline crystals in parallel growth. They show faces of the Baveno twin. The microcline crystals from this quarry are a classic of Catalan mineralogy. Currently works are abandoned and it is difficult to find new specimens.
Smoky quartz crystals with parallel growths. Smoky tone is good. The quartz crystals from this quarry are a classic of Catalan mineralogy. Currently quarry is abandoned and it is difficult to find new specimens.
A rich group of epidote crystals of a very good size and an intense green, almost black color. The crystals show very well defined prism faces of different orders. This crystal shape is quite unusual for this Moroccan locality.
Rich specimen formed by numerous isolated fluellite crystals and forming groups, with a pink to violet color, an unusual fact since fluellite is usually colorless. It is accompanied by whitish to slightly greenish growths of metavariscite. Under magnification we can observe globules of this last phosphate. These specimens are a classic of mining in Navarra and are currently only available through old collections.
These specimens from the La Viesca mine are very rare and appeared in the middle of the last decade. It is a very bright specimen formed mainly by cubic fluorite crystals with polysynthetic growths on the faces and asymmetrically beveled edges, transparent and colorless. They are accompanied by bright and well-defined chalcopyrite crystals, along with complex and transparent honey-colored crystals of sphalerite. With galena and quartz. Highly prized for their rarity.
Specimen formed by numerous globular aggregates of talc, silky and slightly yellowish, which are accompanied by honey-colored dolomite crystals. A very aesthetic and old specimen for this mine from León.