Rosell Minerales

Group of diopside crystals with an intense green color, parallel growths, brilliant and translucent. A specimen of this classic Spanish locality from the Peter Seroka collection.

Col. Peter Seroka, #430 (Girona).

Rich group of tabular semseyite crystals forming brilliant rosettes. It is accompanied on the matrix with galena, chalcopyrite, sphalerite and some quartz. Nowadays, these specimens are not easy to find.

Size: 10.8 x 8.5 x 3.7 cm.

Ex. Jordi Fabre #N23E.

Cuprodongchuanite is a mineral species with the formula Pb₄CuZn₂(PO₄)₄(OH)₂ that has been approved very recently (IMA No. 2021-065); is the copper analogue of dongchuanite (IMA No. 2021-058) with the formula  Pb₄ZnZn₂(PO₄)₄(OH)₂. Both species form a series and belong to the dongchuanite group, together with the zheshengite Pb₄ZnZn₂(AsO₄)₂(PO₄)₂(OH)₂ and the cuprozheshengite Pb₄CuZn₂(AsO₄)₂(PO₄)₂(OH)₂. Distinguishing one species from another is only possible by elemental analysis. For this reason these specimens have been analyzed by SEM-EDS.

In this specimen we have determined the cuprodongchuanite. The presence of As is detected in all the specimens studied, which would indicate that we are in a term of the series with cuprozheshengite. It would be correct to label it cuprodongchuanite-cuprozheshengite. It appears as light green globular aggregates on the colorless hemimorphite. The bluish color on the specimen is veszelyite.

 

Size: 2.2 x 2.1 x 1.2 cm.

Type Locality

Cuprodongchuanite is a mineral species with the formula Pb4CuZn2(PO4)4(OH)2 that has been approved very recently (IMA No. 2021-065); is the copper analogue of dongchuanite (IMA No. 2021-058) with the formula Pb4ZnZn2(PO4)4(OH)2. Both species form a series and belong to the dongchuanite group, together with the zheshengite Pb4ZnZn2(AsO4)2(PO4)2(OH)2 and the cuprozheshengite Pb4CuZn2(AsO4)2(PO4)2(OH)2. Distinguishing one species from another is only possible by elemental analysis. For this reason these specimens have been analyzed by SEM-EDS.

In this rich specimen we have determined cuprodongchuanite aggregates. The presence of As is detected in all the specimens studied, which would indicate that we are in a term of the series with cuprozheshengite. It would be correct to label it cuprodongchuanite-cuprozheshengite. It occurs as light green globular aggregates on very well defined veszelyite crystals and on a matrix with hemimorphite.

Size: 3 x 2.2 x 1.4 cm.

Type Locality

Cuprodongchuanite is a mineral species with the formula Pb₄CuZn₂(PO₄)₄(OH)₂ that has been approved very recently (IMA No. 2021-065); is the copper analogue of dongchuanite (IMA No. 2021-058) with the formula  Pb₄ZnZn₂(PO₄)₄(OH)₂. Both species form a series and belong to the dongchuanite group, together with the zheshengite Pb₄ZnZn₂(AsO₄)₂(PO₄)₂(OH)₂ and the cuprozheshengite Pb₄CuZn₂(AsO₄)₂(PO₄)₂(OH)₂. Distinguishing one species from another is only possible by elemental analysis. For this reason these specimens have been analyzed by SEM-EDS.

In this specimen we have determined the cuprodongchuanite. The presence of As is detected in all the specimens studied, which would indicate that we are in a term of the series with cuprozheshengite. It would be correct to label it cuprodongchuanite-cuprozheshengite. It appears as light green globular aggregates on the colorless hemimorphite. The bluish color of the specimen is due to the fact that the hemimorphite covers veszelyite crystals.

Size: 6.2 x 4 x 2.8 cm.

Type Locality

Very good size specimen of celestine from this classic Spanish locality. In this specimen we can observe various botryoidal to stalactitic forms, one of them in the form of a bridge-curl, and which cover old celestine crystals, as evidenced by the rounded prismatic shapes.

Size: 14.2 x 12 x 5.7 cm.
Found in ±2006.

Specimens of bavenite from Cadalso de los Vidrios are a classic of Spanish mineralogy and pieces of this beryllium and calcium aluminosilicate had not been seen for quite some time. In this good-sized specimen formed by parallel growths of microcline crystals with albite, we can observe numerous rosette-shaped aggregates of tabular bavenite crystals, well defined, brilliant, and colorless to slightly yellowish. The specimen belongs to a North American collection.

Size: 12.1 x 9 x 5.8 cm.

Col. Erich Laskowski.
Classic locality

Rich group of quartz crystals, translucent to hyaline, and with the terminal faces of the rhombohedron different from the usual ones. Among them, a very good size doubly terminated crystal stands out, well defined and with the faces of the prism with striations perpendicular to the main axis. They are disposed on a matrix with quartz and sphalerite crystals.

Size: 11.7 x 8 x 7.4 cm.
Main crystal: 10.9 x 1.5 cm.

A very good size specimen formed by several vugs covered by rosettes of hureaulite crystals with a tabular shape. Crystals are transparent to translucent, well-defined and with a very characteristic light brown color. The matrix is formed by other phosphates such as rockbridgeite, almost black in color. Specimens of this quality and with this size are not easy to find. A museum piece.

Size: 10.6 x 10.5 x 5.8 cm.

This sample comes from the Freiberg Bergakademie and is accompanied by a label from the end of the 19th century and beginning of the 20th. In this old label we can read that the specimen was identified as monazite. To corroborate this fact together with the other accompanying minerals, we proceeded to carry out analyzes by SEM-EDS. The results indicated that the crystals from honey to dark tones, with a vitreous luster, correspond to monazite-(Ce), which is accompanied by rare earth elements such as neodymium or lanthanum, replacing cerium. We also detected the presence of thorium, which explains why the piece shows some radioactive activity. In the potassium feldspar matrix, with quartz, we can observe small black crystals with a metallic luster that would correspond to members of the columbite-(Fe)-columbite-(Mn) series. We have also detected a thorium phosphate-silicate with REE and aluminum traces, with a composition similar to enalite, an independent member of the xenotime-thorite group, although we have not been able to confirm it. We will send the buyer all the analyzes that give this specimen a remarkable mineralogical value.

Size: 6.4 x 5.2 x 3.5 cm.
Found in s. XIX.

Freiberg Bergakademie
Analyzed specimen with report

This specimen from the Freiberg Bergakademie is accompanied by a very old label, probably from the early to mid-19th century, along with a more "modern" one. When in doubt about the description of the labels, we proceeded to analyze the specimen using SEM-EDS. By this spectroscopic technique we have been able to confirm that the beige crystals included in the piece are titanite. The white matrix corresponds to potassium feldspar, most likely microcline, and the black elongated prismatic crystals correspond to aegirine-augite. It is a historical specimen from a Norwegian locality known for centuries for mining magnetite in skarns. We will send all analyzes to the buyer.

Size: 7 x 6.1 x 3.9 cm.
Main crystal: 18 mm.
Found in s. XIX.

Freiberg Bergakademie.
Analyzed specimen with report

These specimens, although not remarkable for their great beauty, do present historical interest to many collectors. According to the old label that accompanies it, the place where it was collected indicates that it is the "pic d'Espada" (Sword peak) and in French territory. After several inquiries, we can place this peak in the Varètja area, in the French High Pyrenees, in Occitania, north of the Spanish border with the Ordesa y Monte Perdido National Park. We can observe numerous black dodecahedral crystals of andradite-grossular, melanite variety, which in the past were given the name "pyreneite". It is accompanied by the 19th century handwritten label of Dr. Hugo Francke (Dresden).

Size: 4 x 3.6 x 3.4 cm.
Found in ±1890.

Freiberg Bergakademie - Dr. Hugo Francke
Analyzed specimen with report

Specimen of hydromagnesite formed by various globular aggregates of lanceolated and transparent crystals of this magnesium hydroxylcarbonate. They stand out for their contrast with the ophiolitic rocky matrix. It is not very common to find specimens from this Italian locality.

Size: 5.7 x 4.4 x 3.4 cm.

This wulfenite specimen comes from the type locality for the species and it is not very common to find specimens from Bad Bleiberg. Wulfenite was precisely renamed in 1845 in honor of Franz Xaver von Wulfen (1728-1805), botanist, mineralogist, mountaineer and member of the Society of Jesus. Wulfen is the author of a monograph on the Bleiberg lead deposits (Austria). This specimen shows us a rich group of sharp dipyramidal crystals, with small tetragonal prism faces. Some of them have complex terminal faces. The orange color and the brilliance of the crystals make it stand out on the matrix. It is accompanied by the handwritten label of Dr. Joan Viñals and belongs to the Marí-García collection.

Size: 8 x 7.3 x 3.8 cm.
Main crystal: 4 mm.
Found in ±1999.

Col. Miquel Marí-Ana García (Castelló)
Type Locality

Superb specimen of heulandite with aggregates of crystals up to 4 cm long, very well defined, translucent, faceted and in parallel growth. They present inclusions of celadonite, a species on which they stand out. An undamaged specimen of considerable size. The collection label will be send to the buyer.

Size: 9.5 x 8.8 x 5.7 cm.
Main crystal: 4.2 cm.
Found in ±2006.

Col. Miquel Marí-Ana García (Castelló)

The chabazite-Ca specimens from this Italian locality present aggregates of orange lenticular crystals. The aesthetic is very remarkable when contrasting in the vacuoles of the basaltic matrix. They are accompanied by phillipsite, analcime, minerals from the smectite group, and calcite. Under magnification we can observe the vacuoles with the different minerals, an entertainment.

Size: 6.8 x 4.8 x 4.6 cm.
Main crystal: 6 mm glob.

The chabazite-Ca specimens from this Italian locality present aggregates of orange lenticular crystals. The aesthetic is very remarkable when contrasting in the vacuoles of the basaltic matrix. They are accompanied by phillipsite, analcime, minerals from the smectite group, and calcite. Under magnification we can observe the vacuoles with the different minerals, an entertainment.

Size: 7.8 x 6.2 x 5 cm.
Main crystal: 4 mm. glob.

Lorenzenite is a rare sodium titanium silicate found in nepheline pegmatites and syenites. In this specimen we can enjoy two bright, well-defined, brown crystals on matrix. A specimen from the Joan Astor Collection.

Size: 4.6 x 3.7 x 2.5 cm.
Main crystal: 10 mm & 7 mm.
Found in ±1990.

Col. Joan Astor (Barcelona).

Specimen upholstered by numerous libethenite crystals, they are accompanied by pseudomalachite. Under magnification we observe pseudooctahedral forms, with brightness and an intense green color. From this classic Portuguese locality.

Size: 5.1 x 4.8 x 3.3 cm.

Radiated spray aggregates of fine dawsonite crystals, a rare aluminum sodium hydroxylcarbonate. They aredisposed on a marl matrix. They come from a known area for the species but from a new find.

Size: 7 x 5 x 1.8 cm.
Found in 2021-22.

Malachite stalactite with a very, very curious shape. Smooth on one side, with brilliant microcrystals of the same mineral. On the other side, it presents an elongated cavity formed by various growths. Floater, good size and quality.

Size: 14.5 x 3.9 x 3.6 cm.

Stalactitic malachite growths, with an intense color, brilliant, velvety and disposed aerially on the matrix.

Size: 12.2 x 6 x 5.2 cm.
Main crystal: 3.8 cm stal.

Stalactitic malachite growths, with an intense color, brilliant, velvety and disposed aerially on the matrix.

Size: 11 x 7.7 x 4.4 cm.
Main crystal: 3.9 cm. stal.

Dadsonite is a rare chloro-sulfoantimonide of lead, compositionally differing from boulangerite by this chlorine anion (1 atom of Cl for 60 atoms of S!). In the "bad-lands" area of Sant Ponç (or Saint-Pons) there are lenticular levels of siderite and calcite. The formation of this rare sulfosalt is based on the redissolution of other sulfosalts in the presence of chlorides.
The fine needles of dadsonite usually appear included in calcite, along with boulangerite. Once the calcite is removed by chemical processes, needles emerge in all their beauty. It can also be found forming radial aggregates in matrix cavities. The dadsonite from Sant Ponç can probably be considered among the best worldwide.

Size: 5.5 x 5.2 x 3.5 cm.
Found in ±1997.

Classic locality

Dadsonite is a rare chloro-sulfoantimonide of lead, compositionally differing from boulangerite by this chlorine anion (1 atom of Cl for 60 atoms of S!). In the "bad-lands" area of Sant Ponç (or Saint-Pons) there are lenticular levels of siderite and calcite. The formation of this rare sulfosalt is based on the redissolution of other sulfosalts in the presence of chlorides.
The fine needles of dadsonite usually appear included in calcite, along with boulangerite. Once the calcite is removed by chemical processes, needles emerge in all their beauty. It can also be found forming radial aggregates in matrix cavities. The dadsonite from Sant Ponç can probably be considered among the best worldwide.

Size: 4.8 x 4.5 x 2.3 cm.
Found in ±1997.

Classic locality