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Group of prase quartz crystals, with good luster, very well defined and contrasting on a matrix covered by andradite crystals. A very aesthetic piece.
Doubly terminated crystal of prase quartz, with a very good size. It shows an intense green color and polycrystalline growths on the faces of the prism. Very aerial and esthetic specimen on a matrix rich in small andradite crystals and green hedenbergite needles. A very aesthetic piece.
Doubly terminated smoky quartz crystal, very well defined, brilliant and transparent. It is disposed on a matrix with adularia crystals.
These pyrite specimens from this Bulgarian mining area are very aesthetic, highlighting the complex forms and penetration twins they present. Good luster and color. They are accompanied by crystals of quartz, sphalerite and brilliant chalcopyrite on the matrix. It comes from a mining area known as the Septemvri mine, which includes the following deposits: Sharenka, Baram, Mogilata, Osikovo and Pechinsko.
These pyrite specimens from this Bulgarian mining area are very aesthetic, highlighting the complex forms. Good luster and color. They are accompanied by crystals of quartz, sphalerite and brilliant chalcopyrite on the matrix. It comes from a mining area known as the Septemvri mine, which includes the following deposits: Sharenka, Baram, Mogilata, Osikovo and Pechinsko.
These pyrite specimens from this Bulgarian mining area are very aesthetic, highlighting the complex forms and penetration twins they present. Good luster and color. They are accompanied by crystals of quartz, sphalerite and brilliant chalcopyrite on the matrix. It comes from a mining area known as the Septemvri mine, which includes the following deposits: Sharenka, Baram, Mogilata, Osikovo and Pechinsko.
Group of smoky quartz crystals of a very good size, complete, doubly terminated and with parallel growth. With transparence and brilliance and a uniform smoky tone. It comes from this classic Swiss locality.
Very good specimen of epidote from this classic Alpine Italian locality. Several epidote crystals with a yellowish green color, with transparence and very well defined. They are accompanied by numerous prismatic crystals of diopside, also very well defined, with transparence, brilliance and a very characteristic olive green color. Good size and quality specimen for display. It belongs from the former collection of Ezio and Manuela Bernabé, with the typewritten label, we will send with the piece.
Hambergite is a rare mineral species, a beryllium hydroxyborate, which occurs in the tourmaline pegmatites of Anjanabonoina. This sample shows us a group of crystals of exceptional size and quality, flattened and with well-defined terminations. Transparent to translucent, with brilliance. This mineral is usually found as single crystals, rarely on matrix, and less with this size. A museum piece.
Exceptional very good sized specimen of humite, a rare magnesium fluorosilicate, from the type locality for the species: Monte Somma. In the piece we can see numerous crystals of an orange tone, defined and some with rounded shapes, brilliant and with transparence. They are accompanied by micaceous phlogopite crystals and white aggregates of sodalite.
Humite is a species closely related to norbergite, chondrodite and clinohumite. These minerals are very difficult to distinguish. Humite appears to have a smaller field of stability than clinohumite, chondrodite and norbergite. Humite is often associated with one or more of the other species of the humite group, as intergrowths.
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.
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.
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.