Exceptional specimen of kolwezite, which occurs as globular aggregates of olive-green crystals, partially covered by a yellowish earthy patina. They are disposed on a matrix of pink crystals of cobaltoan calcite. An exceptional sample for the species. We have analyzed it to check the content of Co. The average of various analyzes indicates a Co: Cu ratio of 1: 2.3-2.6, consistent with some results from other specimens with 1: 2 ratios. Various black aggregates appear in the sample, sometimes partially covering kolwezite, which corresponds to heterogenite. Also with small malachite crystals.

A novelty from the Bleida mines. Groups of malachite crystals, prismatic to needle like, forming velvety aggregates with intense brilliance and color. They are disposed in the cavities of a quartz and dolomite matrix, with chalcopyrite and bornite.

Group of andradite crystals, melanite variety, which show very well defined forms of the dodecahedron, truncated at the edges by those of the trapezohedron. Intense black color, with semi-dull luster.

A good size crystal of andradite, melanite variety, which shows very well defined forms of the dodecahedron, truncated at the edges by those of the trapezohedron. Intense black color, with brilliance.

Group of andradite crystals, melanite variety, which show very well defined forms of the dodecahedron, truncated at the edges by those of the trapezohedron. Intense black color, with a semi-matte luster, and small goethite coatings.

Group of cubic to prismatic fluorite crystals, with a semi-matte luster, transparent to translucent. They are arranged very aerially on a matrix of baryte crystals. From this classic Moroccan mines.

Group of fluorite crystals, very brillinat, with marked color zoning, more intense on the edges. The cube faces show highly aesthetic polysynthetic growths. They are disposed very aerially on a matrix with scalenohedral calcite crystals and small quartz druses. From this classic Moroccan locality.

Rich group of fluorite crystals that show us forms of the cube truncated by those of the octahedron. Very good transparence and with staggered growths on the edges. The violet color with zoning stands out in this specimen, intense on the faces of the cube and almost colorless when we observe those of the octahedron. A very interesting specimen. On a small matrix of dolomite.

A huge size crystal of betafite showing defined octahedral faces (triangular) and developed dodecahedral ones. Very interesting for its crystallography and species. An oldie, classic and representative for the species.
Although the term betafite was discredited in 2010, many of us still are using this term to define this mineral when we see it. Our specimen is an uranium, calcium, titanium and niobium/tantalum oxide with radioactive activity. Currently the betafite is included as a variety within the pyrochlore supergroup. As a note, the rich uranium term has been only found in the Moon (oxyuranobetafite).

Group of cubic fluorite crystals with transparence and a very aesthetic yellowish-green tone. This specimen is tagged as belonging from Wales, but we have not found information on similar specimens. The piece, from the Joan Astor collection, dates from 1975 and was acquired from Sr. Montal. It is most likely an ancient specimen from the Weardale mines.

Sold

This quartz specimen shows an aesthetic group with an excellent transparence and are very well defined faces and edges. It is not common to find with this configuration and less from this Colombian mine.

This group of hyaline quartz crystals belongs from the Cabiche mine, very sharp, with exceptional transparency and luster. They show parallel and at the same time crossed growths. Quartz specimens from this Colombian mine, located in the Boyacá emerald mining area, have been well known since the end of the last century.

Quartz specimens from this Colombian mine, located in the Boyacá emerald mining area, have been well known since the end of the last century. By 2017, new galleries were opened those located different geodes. These crystals, called "mango quartz" or "crown quartz" were found in them, with inclusions that, after being recently analyzed, were determined as halloysite. The inclusions show filamentous structures and the tips of the crystals turn to orange tones. On our website we have already sold some samples with these inclusions on sale, without the orange coloration. Really aesthetic and on a matrix with goethitized dolomite-siderite.

Quartz specimens from this Colombian mine, located in the Boyacá emerald mining area, have been well known since the end of the last century. By 2017, new galleries were opened those located different geodes. These crystals, called "mango quartz" or "crown quartz" were found in them, with inclusions that, after being recently analyzed, were determined as halloysite. The inclusions show filamentous structures and the tips of the crystals turn to orange tones. On our website we have already sold some samples with these inclusions on sale, without the orange coloration. Really aesthetic and on a matrix with goethitized dolomite-siderite.

Quartz specimens from this Colombian mine, located in the Boyacá emerald mining area, have been well known since the end of the last century. By 2017, new galleries were opened those located different geodes. These crystals, called "mango quartz" or "crown quartz" were found in them, with inclusions that, after being recently analyzed, were determined as halloysite. The inclusions show filamentous structures and the tips of the crystals turn to orange tones. On our website we have already sold some samples with these inclusions on sale, without the orange coloration. Really aesthetic and on a matrix with goethitized dolomite-siderite.

Quartz specimens from this Colombian mine, located in the Boyacá emerald mining area, have been well known since the end of the last century. By 2017, new galleries were opened those located different geodes. These crystals, called "mango quartz" or "crown quartz" were found in them, with inclusions that, after being recently analyzed, were determined as halloysite. The inclusions show filamentous structures and the tips of the crystals turn to orange tones. On our website we have already sold some samples with these inclusions on sale, without the orange coloration. Really aesthetic and on a matrix with goethitized dolomite-siderite.

Goethite specimen from this classic French mine, now closed and partially restored, which shows druses of goethite small crystals, defined and very, very bright. Under loupe is incredible. The sparkles of the crystals in the light are spectacular. The specimen was analyzed by Raman spectroscopy to confirm the species.

Sold

Quartz specimen with groups of crystallized gold. It is accompanied by galena and grey cosalite needles (a bismuth and lead sulfosalt). A gold curiosity of this French mine that was precisely exploited by the "Société des Mines du Bourneix" for the extraction of gold.

Specimen formed by several interpenetrating davidite-(La) crystals. We can observe various curved, shiny facets of this rare species, from the crichtonite group, and of a complex formula with an unique combination of elements:  La(Y,U)Fe₂(Ti,Fe,Cr,V)₁₈(O,OH,F)₃₈.
It belongs from the type locality for the species: Radium Hill. To confirm the species we have carried out SEM-EDS analysis with results consistent with expectated. It is not easy to find specimens of the type locality and less with facets.

Sold

Specimen formed by several interpenetrating davidite-(La) crystals. We can observe various curved, shiny facets of this rare species, from the crichtonite group, and of a complex formula with an unique combination of elements:  La(Y,U)Fe₂(Ti,Fe,Cr,V)₁₈(O,OH,F)₃₈.
It belongs from the type locality for the species: Radium Hill. To confirm the species we have carried out SEM-EDS analysis with results consistent with expectated. It is not easy to find specimens of the type locality and less with facets.

Sold

Goethite specimen from this classic French mine, now closed and partially restored, which shows druses of goethite small crystals, defined and very, very bright. Under loupe is incredible. The sparkles of the crystals in the light are spectacular. The specimen was analyzed by Raman spectroscopy to confirm the species.

Sold

Quartz specimens from this Colombian mine, located in the Boyacá emerald mining area, have been well known since the end of the last century. By 2017, new galleries were opened those located different geodes. These crystals, called "mango quartz" or "crown quartz" were found in them, with inclusions that, after being recently analyzed, were determined as halloysite. The inclusions show filamentous structures and the tips of the crystals turn to orange tones. On our website we have already sold some samples with these inclusions on sale, without the orange coloration. Really aesthetic and on a matrix with goethitized dolomite-siderite.

Brilliant specimen formed by a druse of defined tarpezohedral crystals of grossular, hessonite variety. Intense color, shine and transparence. It is accompanied by groups of green clinochlorine crystals.

Elongated cubic fluorite crystal of very good size, with tile growths on the faces. Between translucent to transparent and with a very uniform violet color. It is complete on both sides and is placed on a small matrix with quartz.

Very interesting specimen of elbaite that has been partially transformed into lepidolite. A Brazilian curiosity. It comes from the Joan Astor collection (Barcelona), with a handwritten and typewritten label.

Sold