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In this specimen we can observe an idiomorphic good size crystal of tapiolite-(Fe), Fe²⁺Ta₂O₆, that shows us different tetragonal faces. Good luster, intense black colour with iridescence on faces. It stands out on a matrix with albite and muscovite. The analyzes carried out indicate the presence of niobium in small proportions. These results will be sent to the buyer of the specimen.
Specimen formed by various aggregates of sheaf-shaped ushkovite crystals, with a distinctive orange color. It is a rare phosphate with the formula MgFe³⁺₂(PO₄)₂(OH)₂·₈H₂O. They are arranged on a matrix of roscherite and rockbridgeite, with white crusts of uralolite and possibly small colorless beryllonite crystals. A very interesting specimen due to the rarity of the minerals present.
Acute, yellow to orange, transparent, dipyramidal powellite crystals. Accompanied by molybdenite in the matrix. Very fluorescent under UV short wave, with yellow tones.
Acute, yellow to orange, transparent, dipyramidal powellite crystals. Accompanied by molybdenite in the matrix. Very fluorescent under UV short wave, with yellow tones.
Group of rhombohedral calcite crystals of very good size, with defined faces and edges, with interpenetration twins. Slightly pinkish white in colour, matt faces. This specimen stands out for its intense fluorescence and more than notable fluorescence when illuminated with UV-LW light. It comes from the Jaime Murria collection (Barcelona).
Group of geocronite-jordanite crystals, with striated pseudohexagonal shapes, very bright and rich in facets. The matrix is mainly composed of geocronite-jordanite, with various cavities where we observe striated crystalline faces.The analyzes show a correlation between geocronite-jordanite, both are isostructural and form series. Crystals analyzed show that the composition moves in the intermediate zone of the series. The geocronite-jordanite crystals are accompanied by sphalerite, galena, associated with transparent crystals of green fluorite.
Old specimen of rhodonite from this Peruvian mine. Formed by parallel growths of tabular crystals, with a soft pink color and shine. With pyrite in matrix.
This is a rich and a huge size specimen of one of the most unique species in all the mineral kingdom. Cylindrite is a lead, iron, tin, antimony sulfosalt that forms in "cylinder" or "tube" shaped crystals, hence the name. In fact, this species belongs to the only group of minerals that naturally forms rounded, curved or tubular shaped crystals. This specimen is especially nice considering that it is loaded with crystals. The mine at Poopo is the type locality for the species. A museum specimen.
Good size heliodor crystal. With a greenish yellow color, transparent to translucent, with some faces, some rounded and others more defined. A gem with the old label of former Lloid, by Hortensia Durán y Marçal Llòria (Barcelona). Photo is not very representative of the brilliance and transparence.
Group of orange quintinite crystals (quintinite-2H polytype, Mg₄Al₂(OH)₁₂(CO₃)·₃H₂O) disposed on a matrix with strontianite. Very rare species belonging to the hydrotalcite supergroup.
This topaz specimen shows us some interesting inclusions oriented in the cleavage plane (001). Transparency is complete. With label from Juan Montal, former mineral dealer from Vilafranca del Penedés (Catalonia).
Good sized topaz crystal, colorless, richly faceted, brilliant, colourless and very transparent. It has some chips, but it is a gem.
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.
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.
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.
Group of childrenite crystals, well defined, transparent to translucent, accompanied by aggregates of polythionite (mica group). They are disposed on a matrix with feldspar and quartz.
Drusy crystals of yellow-green (var. cuprian) powellite. Good sized crystals and with rounded faces. Fluoresces bright yellow under SW-UV light. This mine is the Type Locality for szenicsite.
Very rich druse of pseudomalachite crystals of intense green color, forming defined, translucent prismatic tabular crystals. Specimens of this species in this mine are rare. The piece belonged to the E. Laskowski collection (Tucson, USA), with the seller's label. Very interesting specimen.
Olive green prismatic olivenite crystals are arranged on a goethite matrix, along with dark green cornwallite and light green malachite aggregates. Brazil seems to have a little bit of everything when it comes to deposits, and even though it's best known for it gem pegmatites, there are all sorts of curious localities like Ibiajara where copper minerals (and even a little gold) have been found.
A very rich specimen of lammerite aggregates, green in color, in several geodes we can observe crystals of this rare copper arsenate. It is accompanied by groups of blue lemanskiite crystals (previously identified as lavendulana).
These specimens from the Siglo XX Mine present defined, brilliant, translucent and light orange colour monazite-(Ce) crystals. They are accompanied by hyaline quartz and black-brown cassiterite on matrix. Some are twinned. Monazite is found in small quantities in this mine.
Monazite gets its name from the Greek word μουάζω "monazein" meaning "to be alone," alluding to its isolated crystals and their rarity when they were first found. Monazite is generally found in granitic pegmatites, but these crystals are found in hydrothermal veins with tin and the absence of thorium (generally an accompanying element of monazite).
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.
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.
Druse formed by numerous globular aggregates of greenish-brown zanazziite disposed on a pegmatitic matrix with muscovite. Zanazziite is a rare hydrated calcium, magnesium, iron, aluminum and beryllium phosphate. With a handwritten label.
A very good-sized specimen of atacamite formed by numerous radial aggregates of tabular crystals, of intense green colour and transparence, which are disposed on a matrix with chrysocolla and malachite. This specimen has both sides worthy of a display case. It is accompanied by the handwritten label of Joan Viñals.