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     Several ilvaite crystals on a druse of quartz crystals, with an intense black color, doubly terminated and twinned. Observing with the magnifying glass we can see perfect doubly terminated crystals, a pleasure. They are arranged in a very aerial way giving the specimen a notable elegance.
A very aesthetic specimen of what are some of the most iconic cassiterites in the world, and certainly the most famous from Europe: Schlaggenwald (nowadays Horni Slavkov), have such an iconic appearance and this piece is no exception. It features a predominant, sharp, lustrous, cyclic twinned group crystals, in unusual peaked formation (result of twinning).


These hematite crystals from a quarry near Nador are already a classic of Moroccan mineralogy. This specimen is made up of various crystals in parallel growth, with exceptional brilliance, and showing the faces of different crystals. Its size and quality and metallic luster make them a definitive specimen from this locality. These hematites come from a small rhyolite quarry very near the community of Nador, on the road to Melilla.


Group of carrollite crystals showing cube and octahedron shapes. Very bright and interpenetrated with each other. Defined edges and faces and exceptional shine. Very aesthetic.
The tin mine at Viloco (sometimes called Araca) has produced some of the most magnificent cassiterite specimens worldwide, and a very small percentage of these pieces are actually associated with tourmaline. This specimen hosts a few fine, sharp, lustrous, translucent, brown/black cyclic twinned crystals of cassiterite with small quartz crystals and small acicular greenish-black crystals of tourmaline (dravite?). This association is seen in only a handful of cassiterite specimens from this historic locality.


In this specimen we can observe two very well defined anatase crystals, with the shapes of the tetragonal dipyramid truncated at the vertices by pinacoidal faces. The shine is excellent and they have an almost black color but with navy blue reflections when the light hits them. They are arranged in a very aerial way on a rock matrix covered by small tabular b alvite crystals between transparent and translucent and very brilliant.
Group of skutterudite crystals of very good size, exceptional brilliance and forming parallel growths that resemble a rosette. An excellent piece from this classic Moroccan locality that surpasses many of the specimens I have seen.
Very rich group of mimetite crystals, with an intense orange color, luster and transparency, with interpenetrated hexagonal crystals truncated by the pinacoidal faces.
Very aesthetic specimen formed by several prismatic fluorapatite crystals with hexagonal forms, showing short prisms of various orders, truncated by developed pinacoidal faces. The brilliance and transparence are excellent. They present a violet-blue color zoning depending on the light that falls on them. They are disposed in a very aerial way on a matrix with muscovite, siderite and well-formed arsenopyrite crystals.


Group of carrollite crystals showing cube and octahedron shapes, along with tetrahexahedron shapes. Very bright and interpenetrated with each other. Defined edges and faces and exceptional shine. Very aesthetic.
The silver specimens from this classic German mine has been known for a long time, but in these specimens silver is included in chrysocolla, of an intense greenish blue colour, and shows a remarkable luster, sometimes with golden iridescence. Under magnification we can see facets of crystals of this metal. We have analyzed these samples and the results indicate that they do not contain other metals detectable by SEM-EDS. These specimens are already a few years old.
Parallel growth of hübnerite crystals, of very good size, with evident reddish reflections. With defined terminal faces, translucent on edges and with brilliance. With hyaline quartz crystals. Excellent old piece from this Peruvian mine.
Old specimen of blue fluorite from this mining area in the central-eastern United States. Fluorite crystals have partially corroded cubic shapes. It is accompanied by a galena crystal covered with tiny cerussite crystals. With an old Enric Kucera label.
Lanceolated hemimorphite crystals, defined, brilliant, colorless and transparent. They are arranged in a limonite-goethite matrix. Classic and aesthetic material from this famous Mexican mine, from the E. Nicolau collection (Barcelona).
On a matrix formed by orthoclase crystals, numerous titanite crystals are arranged, yellowish olive green in color, transparent to translucent, with brilliance and defined faces and edges. A classic specimen from this Moroccan mining area.
Large group of bournonite crystals, brilliant, with complex and interpenetrated faces. They are accompanied by honey tone sphalerite crystals. The specimen is accompanied by a label that identifies it as from Saint-Laurent-Le-Minier (Sent Laurenç del Minièr), although it is more likely that it is from the Saguinede mine in Montdardier, very close to Saint-Laurent.
Druse of prismatic acicular pyromorphite crystals, transparent, shiny and with the characteristic green color. They are arranged on a quartz matrix. A very aesthetic piece from the Nicolau collection (Barcelona) and with a Joan Viñals label.
In this specimen, obtained in the Manzanera cemetery area, we can observe numerous calcite crystals with quartz, some hematite crystal and, hidden, a yellowish fluorapatite crystal, well defined and transparent. Unique specimen from a very little-known locality.
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.
La dadsonita es un raro cloro-sulfoantimoniuro de plomo (1 átomo de cloro por cada 60 de azufre), composicionalmente difiere de la boulangerita por este anión de cloro. En la zona de las "bad-lands" de Sant Ponç (o Saint-Pons) se encuentran niveles lenticulares de siderita y calcita. La formación de esta rara sulfosal se basa en la redisolución de otras sulfosales en presencia de cloruros.
Las finas agujas de dadsonita suelen aparecen incluídas en calcita, junto con boulangerita. Una vez la calcita se elimina mediante procesos químicos als finas agujas afloran en toda su belleza. También se la puede encontrar formando agregados radiales en cavidades de la matriz. Probablemente, la dadsonita de Sant Ponç puede considerarse entre las mejores del mundo.
Anglesite specimens from this classic Moroccan mine are quite difficult to find. In this piece we can see numerous lanceolated prismatic crystals of this lead sulphate, very brilliant, with well defined faces and edges, transparent and showing the natural yellow colour characteristic of this species and mine. They are disposed filling cavities in a galena matrix.
Cluster of aragonite crystals, very bright and defined. They are known in the area as "sputnik stones" (sic) because of their appearance. They present a color zoning on the surface, between gray and brown. They are floating. A Moroccan curiosity.
Cluster of aragonite crystals, very bright and defined. They are known in the area as "sputnik stones" (sic) because of their appearance. They present a color zoning on the surface, between gray and brown. They are floating. A Moroccan curiosity.
Group of good-sized sulphur crystals from a classic Spanish locality, but from a little-known mine, showing a great richness of faces, some brilliance and a canary yellow color. It is arranged in a cavity with calcite crystals. A fine Spanish specimen.
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.
