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Curious globular aggregates formed by numerous fluorite octahedral crystals that have grown together, reaching this globular shape. If you look closely under magnification the specimen you can observe different growing phases. So we can see perfect small colorless octahedra, others as groups of a few crystals sharing faces and symmetry, and some with many octahedrons close to this globular shape. Very fluorescent under SW-UV.
This green color is the best ever found for this site, with transparence and brilliance. They are disposed on an matrix of hard porphyry covered by minute quartz crystals, with calcite and goethitized cubic pyrite.
This area is known as Singuerlín (a neighborhood of Santa Coloma de Gramenet city, close to Barcelona) and from 60's collectors has found these globular aggregates with tones between white, yellow or slightly greenish. Then some specimens were analyzed and labeled as gearksutite. More recent analysis did not indicate the presence of this species but only fluorite.
Curious globular aggregates formed by numerous fluorite octahedral crystals that have grown together, reaching this globular shape. If you look closely under magnification the specimen you can observe different growing phases. So we can see perfect small colorless octahedra, others as groups of a few crystals sharing faces and symmetry, and some with many octahedrons close to this globular shape. Very fluorescent under SW-UV.
This green color is the best ever found for this site, with transparence and brilliance. They are disposed on an matrix of hard porphyry covered by minute quartz crystals, with calcite and goethitized cubic pyrite.
This area is known as Singuerlín (a neighborhood of Santa Coloma de Gramenet city, close to Barcelona) and from 60's collectors has found these globular aggregates with tones between white, yellow or slightly greenish. Then some specimens were analyzed and labeled as gearksutite. More recent analysis did not indicate the presence of this species but only fluorite.
Curious globular aggregates formed by numerous fluorite octahedral crystals that have grown together, reaching this globular shape. If you look closely under magnification the specimen you can observe different growing phases. So we can see perfect small colorless octahedra, others as groups of a few crystals sharing faces and symmetry, and some with many octahedrons close to this globular shape. Very fluorescent under LW-UV. This green color is the best ever found for this site, with transparence and brilliance. They are disposed on an matrix of hard porphyry covered by minute quartz crystals, with calcite and goethitized cubic pyrite.
This area is known as Singuerlín (a neighborhood of Santa Coloma de Gramenet city, close to Barcelona) and from 60's collectors has found these globular aggregates with tones between white, yellow or slightly greenish. Then some specimens were analyzed and labeled as gearksutite. More recent analysis did not indicate the presence of this species but only fluorite.
Curious globular aggregates formed by numerous fluorite octahedral crystals that have grown together, reaching this globular shape. If you look closely under magnification the specimen you can observe different growing phases. So we can see perfect small colorless octahedra, others as groups of a few crystals sharing faces and symmetry, and some with many octahedrons close to this globular shape. Very fluorescent under SW-UV.
This green color is the best ever found for this site, with transparence and brilliance. They are disposed on an matrix of hard porphyry covered by minute quartz crystals, with calcite and limonite. also some botryoidal white aggregates of hydrozincite.
This area is known as Singuerlín (a neighborhood of Santa Coloma de Gramenet city, close to Barcelona) and from 60's collectors has found these globular aggregates with tones between white, yellow or slightly greenish. Then some specimens were analyzed and labeled as gearksutite. More recent analysis did not indicate the presence of this species but only fluorite.
Curious globular aggregates formed by numerous fluorite octahedral crystals that have grown together, reaching this globular shape. If you look closely under magnification the specimen you can observe different growing phases. So we can see perfect small colorless octahedra, others as groups of a few crystals sharing faces and symmetry, and some with many octahedrons close to this globular shape. Very fluorescent under SW-UV.
This green color is the best ever found for this site, with transparence and brilliance. They are disposed on an matrix of hard porphyry covered by minute quartz crystals, with calcite and goethitized cubic pyrite.
This area is known as Singuerlín (a neighborhood of Santa Coloma de Gramenet city, close to Barcelona) and from 60's collectors has found these globular aggregates with tones between white, yellow or slightly greenish. Then some specimens were analyzed and labeled as gearksutite. More recent analysis did not indicate the presence of this species but only fluorite.
Group of very sharp fluorite crystals which show good transparency and lilac to purple color. They are disposed on a matrix with feldspar and smoky quartz, accompanied by small prismatic crystals of brilliant prismatic stilbite, transparent and vivid orange color. Also with groups of clinochlore crystals, with dark brown to nearly black color.
This specimen was collected from miarolitic pegmatites veins in granite of the Strzegorn-Sobótka massif quarries. These quarries are worked for aggregates and miarolitic cavities are scarce. These specimens are coveted by collectors, mainly German and Poles, unusual in other collections.
The kamotoite-(Y) are the intense yellow crystalline sprays, with individual flat-laying crystals to 5 mm. In the same sample we can observe probably a small vein of yellow to orange brilliant uranophane.Kamoto is the Type Locality for the species. A very rare uranium and ytrium mineral from Katanga.
Nice specimen from the former mineral collection of Henri-Léon Ungemach (1879-1936). The sample corresponds to the label. Sometimes is difficult this relation, or specimen has no number on or number do not match.
The cavity is covered by scalenohedral calcite crystals, and on them groups of brilliant galena and pyrite. We can observe some idiomorphic crystals, with defined faces and dull luster, of stephanite. A sample with its own history.
Unusually species for this Moroccan mine. The dealer confirmed the locality, I initially thought in Imiter. This is a group proustite crystals with good red color, brilliance and transparence, some of them contacted due to the cavity, others showing terminations and striated faces. In calcite matrix.
A huge size specimen of malachite that has completely replaced azurite former crystals, preserving its prismatic shape, with visible terminal faces. Malachite has an intense green color, with silky luster due to its acicular shape, fibrous. With a minor rocky matrix. An elegant specimen of a classic mine as Touissit.
Let me add another "delicious" specimen of kutnohorita with manganoan calcite. Kutnohorite is a rare member of dolomite group, a calcium carbonate with manganese, magnesium and few iron... uncommon. In the specimen appears as acicular snowy white crystals on which have grown a large group of pink crystals of calcite with manganese. Good brilliance and calcite extremely fluorescent with reddish tone. In the back side we can observe a particular radial aggregates of kutnohorite, this is another shape of the species. We have both in the same sample... The aesthetics of the formations is unquestionable and the species is a classic hard to find.
This huge size specimen combines two very interesting species. On one hand we have spherical aggregates formed by radiated polysynthetic growth of poldervaartite, showing slightly curved top faces, with a very uniform beige and good luster. We would like to inform you that these specimens were found in the mine in late 2010 and were collected very few specimens. They were analyzed by SEM-EDS, and it was found that the external and surface crystals were mainly determinated as poldervaartite, while the inner concentric growths presents poldervaartite and olmiite mixture. This makes us confirm poldervaartite in this mine.
Only for this species this sample is excellent. But it is accompanied by xonotlite, an uncommon calcium silicate, in the form of fine needles, brilliance and flexible. A stunning combination. To increase its interest we can say that this sample is one of the few of this vug, from this popular South African mine. A great opportunity. We will send the analysis to the buyer.
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. This specimen belonged to the collection of P. Sainfeld, mineralogist at the École des Mines de Paris.
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).
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. This specimen belonged to the collection of P. Sainfeld, mineralogist at the École des Mines de Paris.
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).
From a classic German locality: Alberoda bei Aue. This locality is known by its silver sulphosalts, but not well represented in collections. This sample is very rich in brilliant stephanite crystals and some reddish pyrargyrite. An old specimen, old label and quality.
Group of octahedral crystals of this unusual nickel sulfoarsenide. It shows very bright faces and defined edges. The luster, tet me emphasize, is exceptional. Disposed very aerial on a matrix of calcite. This specimen has NOT been acidified to remove calcite as is usual in many specimens what may compromise their future stability. A good choice.
Recent mineral find and novelty at Sainte-Marie-aux-Mines 2013. An rich and aesthetic group of prismatic cerussite crystals, with white color, translucent, brilliant, very acute and complex terminations and good size. With striated faces. Contrasting very aerial on the matrix.
The lead and silver mine of Lescure was worked in Roman times and there are documents from the late eighteenth century telling us about these mines. Although "serious" mining operations are confirmed from 1808-29 until its closure in 1951. These specimens are known in long crystals, and since the 90s had not been obtained pieces of this quality. Today the mine is closed and collapsed (Le Règne Mineral, 85, 2009).
Recent mineral find and novelty at Sainte-Marie-aux-Mines 2013. A very rich group of prismatic cerussite crystals, with white color, translucent, brilliant, very acute and complex terminations and good size. With striated faces. Contrasting very aerial on the matrix.
The lead and silver mine of Lescure was worked in Roman times and there are documents from the late eighteenth century telling us about these mines. Although "serious" mining operations are confirmed from 1808-29 until its closure in 1951. These specimens are known in long crystals, and since the 90s had not been obtained pieces of this quality. Today the mine is closed and collapsed (Le Règne Mineral, 85, 2009).
A novelty at Sainte-Marie-aux-Mines 2013. Globular aggregates of tabular hemimorphite crystals showing an intense blue color and good luster. This blue color is unusual for the species and in relatively few deposits can be observed, it is usually colorless. The specimen is peppered by groups of very sharp cerussite crystals with good brilliance, some of them partially covered bay a black microcrystals, showing prismatic crystals and cyclic twins. From a recent find at the Kimbedi copper mining area in the Republic of Congo (Congo Brazzaville).
A novelty at Sainte-Marie-aux-Mines 2013. Globular aggregates of tabular hemimorphite crystals showing an intense blue color and good luster. This blue color is unusual for the species and in relatively few deposits can be observed, it is usually colorless. The specimen is peppered by groups of very sharp cerussite crystals with good brilliance, some of them partially covered bay a black microcrystals, showing prismatic crystals and cyclic twins. The sample is from a recent find at the Kimbedi copper mining area in the Republic of Congo-Brazzaville.
A high quality specimen from the famous Carrara Marble quarries of Italy. The ancients believed that the water solidified in the form of hyaline quartz crystals... Viewing this specimen, its purity, transparency, brilliance and perfection, perhaps we can understand their interpretation. Undamaged crystals, one almost doubly terminated and on snowy white marble matrix, partially covered by tiny crystals of calcite. An Italian gem.
Group of very sharp quartz crystals with inclusions of clinochore, transparence, luster and aesthetically disposed on a K-feldspar (adularia) crystals as a matrix.Very aesthetic and from a unusual locality.
Interesting specimen of aegirine showing defined prisms with an intense color almost black, brilliance and sharp, prismatic and marked terminal faces. They are accompanied by a some groups of zircon crystals in parallel growth, showing the tetragonal prism and dipyramids. Good orange to yellowish tones, some transparency on edges and disposed in aerial way on aegirine matrix.
On a compact quartz matrix we have different groups of cobaltoan calcite crystals with intense purple to fuchsia color, with transparence and well defined faces and edges. It is accompanied by spherical aggregates of snowy white dolomite and some quartz crystals. A classic from Katanga Copper Crescent mines.
This specimen shows spherical aggregates of plancheite, formed by several acicular crystals in a radiated shape. On the surface of the spheres we can enjoy curious honeycomb structures. Color is between blue and blue-gray. On a vug layered by small quartz crystals. From a locality not well represented in collections for this species.