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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.


A sculptural and highly unusual, layered nodule of botryoidal, lustrous, rich brown, cassiterite from a very uncommon Montana locality. This variety of cassiterite is called "stream tin", due to the rounded, stream-worn character of the cassiterite. Stream tin was named by Cornish miners from the streams, where the rich deposits were first found in Cornwall. This is excellent, old-time material from the Jaime Bird Collection [Rob Lavinsky sold 2009]. It has two labels attached with the numbers 472 and 4240.
"Wood tin," a cryptocrystalline variety of cassiterite, has bands that resemble the age rings of wood. This variety occurs in locations across the globe, and lapidaries sometimes create ornamental objects and cabochons from it.
Very aesthetic specimen from this classic Portuguese mining town that presents us with a large group of fluorapatite crystals, which present prismatic shapes with striated faces and truncated by the pinacoid. Between translucent to transparent and with a marked color zoning of more intense green in the crystal core. The specimen is partially covered with muscovite rosette aggregates. Floating specimen.


Group of stephanite crystals that form a floating cluster, with various interpenetrated prismatic crystals, with defined faces and edges and brilliance. This specimen comes from an unusual Mexican mine for the species and is accompanied by the label of a well-known mineral dealer in Madrid. The piece belongs from the Nicolau collection (Barcelona). A very aesthetic and representative miniature of the species.
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 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.


Very rich group of pyromorphite crystals of intense yellow color with orange tones. These are hexagonal prisms with multiple terminations and transparence and exceptional brilliance. A specimen with some years behind it from this classic North American minning locality.


In this specimen we can enjoy several groups of wire silver, with showy wire to skeletal growths and metallic luster. Accompanied by black acanthite crystal aggregates. From a classic locality for the Catalan and Spanish mineralogy. A good chance to represent this locality in your collection. Nowadays it is very difficult find specimens, only from old collections...
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.
Very rich specimen formed by numerous and brilliant pyrolusite crystals with a tabular appearance and forming globular growths. With Joan Viñals label.
Excellent, pure aesthetics. It is a group of arfvedsonite crystals of intense black color, shiny, with defined and shiny faces, arranged on a matrix of feldspar, orthoclase. From the Nicolau collection (Barcelona), with a handwritten label by Joan Viñals.
A lustrous slightly translucent brown scheelite crystal, this with pale green cubic fluorite crystals at its base. Neat comination piece. From a distinctive and limited find in the late 1990's. With Joan Viñals label. Active under SW-UV light.
A classic specimen with a label from a classic Catalan dealer Sr. Joan Montplet, from "El Filó" in Sant Celoni (Barcelona). A group of green, prismatic crystals of fluorapophyllite-(K), transparence is observed on a matrix of stilbite-Ca crystals. Interesting for its aesthetics and label.
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).
Group of kyanite crystals, of gem quality, with transparency and when light passes through them they offer an exceptional color. They are accompanied on the matrix by brown staurolite crystals and paragonite (Na mica). They stand out on a clear schistose matrix. A quality European piece that is difficult to see today. Classic and aesthetic material from this famous Swiss locality from the E. Nicolau collection (Barcelona).
Globular aggregate of variscite crystals, apple green in color and with transparency and shine, aesthetically arranged in a cavity of the matrix. Uncommon and of good quality for a find from years ago.
Druse of small white crystals of tacharanite (basalt-hosted zeolite) forming aggregates with approximately globular shape, coating a basalt rocky matrix. Really interesting sample and locality.
Druse of small and brilliant vanadinite crystals. A curiosity for collectors of Spanish localities. With the Dr. Joan Viñals label.
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.