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Compact aggregates of pectolite, forming radial aggregates of creamy white color, forming globules interpenetrated between them. On a basalt matrix. Fluorescent under LWUV. It belongs from the Emili Nicolau (Barcelona) collection and was acquired from Joan Viñals in 2003.
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.
Specimen very rich in cassiterite crystals, very bright, richly faceted and of an intense dark brown color. The specimen has been repaired without affecting the interest of the specimen, from my point of view. A very interesting piece from these tin mines of the St Agnes mining district, an English classic.
Silver specimen from this Australian locality formed by numerous groups of silver on twisted wires. It is accompanied by siderite and galena, and probably chlorargyrite. From the Vilaseca collection, Barcelona.
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).


This rare specimen of stibnite has an ancient handwritten label attached indicating the San Pancracio mine in Ceuta. Searching for information about this mine we have found in MTI details of the work: “Síntesis geológica de Ceuta” by Simón Chamorro and Mercedes Nieto (1989) about this town. We reproduce here some of the details indicated in their work: "Next to Arroyo de las Bombas and near Fort Piniers, there is a deposit of antimonite (stibnite), known by the name of San Pancracio. The mineralization is associated with the contact between the warped limestones and the Carboniferous shales and sandstones; both types of rocks appear mineralized, although in the latter with more intensity the main control of the deposit is defined by a fault and a system of associated fractures from directions N 10º E to N 25º. E. [...] It was exploited by Fundiciones de Antimonio S.A. of Barcelona, from 1960 until March 1979, the year in which it was abandoned due to depletion of the main mineralized masses. Its production has been very small, a maximum of 135 t. in 1970, and an average grade of 45% [...] It presents a paragenesis of stibnite-quartz and carbonates, with traces of chalcostibine, galena, pyrite, chalcopyrite, chalcosine, covelline, brandsite and gold. Simón Chamorro Moreno, Mercedes Nieto García (1989): Síntesis geológica de Ceuta. Ceuta. ISBN: 84-87148-07-9.
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.


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.
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.