- Home About RM Minerals
- Virtual Photo Museum Blog RM Contact
- Microscopy and instruments How to Buy Disclaimer
Copyright 2010-2025
www.rosellminerals.com
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.
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.
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.
Stalactitic malachite growths, with an intense color, brilliant, velvety and disposed aerially on the matrix.
Stalactitic malachite growths, with an intense color, brilliant, velvety and disposed aerially on the matrix.
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.
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.
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.
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.
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.
These specimens from this Czech locality were initially cataloged as "hornblende", later studies indicated that it could be kaersutite, a member of the amphibole group. This specimen has a brownish tone that makes us think it could be a pseudomorphosis. It shows very well defined faces that can allow crystallography lovers to measure angles. An old sample.
A specimen of the highest quality for this locality and for the species, named in honour to our colleague D. Antonio Barahona. The species was determined in samples from Pastrana, Mazarrón (Murcia), its type locality, more than a decade ago by Dr. Joan Viñals. This specimen shows various vugs covered by small sky-blue barahonaite crystals. The color is excellent and the size of the sample makes it worthy of a fine showcase. We have also analyzed it and will send the results to the buyer.
Specimen very rich in mimetite crystals, with shapes of the hexagonal dipyramid, some doubly terminated, with a slightly orange-yellow colour, very brilliant. They are disposed on a matrix of goethite with hemimorphite. From an unusual locality for the species. The specimen has been analyzed since it was labeled as pyromorphite. We will send the results to the buyer.
Specimens of fettelite, a complex silver-mercury sulfoarsenide, are very rare and even less so at this size. Under magnification we can observe burgundy red laminar crystals of fettelite, together with idiomorphic crystals of proustite. An exceptional piece.
Scolecite and aerinite specimens from this Aragonese area are known worldwide. This specimen shows us groups of acicular crystals forming radiated aggregates in the dolerite and that, when extracted, allow us to see their internal arrangement perfectly. White in color, with iron oxydes patina, and good brilliance. Samples of this quality and size are not common and even less so today.
The Cyclopean Isles is a small volcanic archipelago off the coast of Aci Trezza, in the Etna volcanic complex. They are the type locality for the analcime species, which we can see in this specimen. This old time sample from the Freiberg Bergakademie shows us vacuoles with idiomorphic analcime crystals accompanied by colorless, well-defined thomsonite-Ca prisms those have grown on the analcime. The two labels give clear testimony to the antiquity of the specimen. A true mineralogical curiosity.
In this specimen from the Bergakademie zu Freiberg we can see several schorl crystals, one of them with a well-defined prism and clearly visible terminal rhombohedral faces. The mica matrix contains reddish almandine crystals. Very interesting handwritten label.
Group of tabular enstatite crystals that have been pseudomorphized by steatite, a variety of talc. Defined, black color and good sized. They are usually accompanied by chloroapatite, beige in color, as we can see in the sample. Specimens from this locality are very rare and even less so with this quality, The mines are now closed and most of the dumps are overgrown by forest. It is accompanied by a handwritten label that we can place at the beginning of the s. XX, from the collection of the Freiberg Bergakademie.
Excellent specimen formed by numerous sheaf aggregates of stilbite (Desmin in the label) crystals. Colourless to slightly yellowish. They are accompanied by smoky quartz crystals, very visible on the backside of the specimen. This piece belongs from the Freiberg Bergakademie, specifically its label tells us that it was sold in the shop that was created to sell minerals, surely for students. The handwritten label can be related to Wilhelm Maucher (maucherite, 1879-1930), a mineralogist and mineral dealer in Munich and who was a "faktor" with the school between 1904 and 1909.
Laminar crystals of kyanite, with a bluish tone, from this deposit located on the road between Canillas del Aceituno and Sedella. This specimen belongs from the Peter Seroka collection and is accompanied by the label.
In this specimen we can enjoy different columbite crystals, one of them predominant, although there are smaller, transparent and reddish ones. The analyzes of the specimen indicate the majority presence of niobium and manganese, so it is a columbite-(Mn) (you can check analysis in pictures). The main crystal stands out for its faceting, it has a small dent without affecting the quality of the piece. It comes from the collection of Michel Jouty (1930-2016).
Druse of jarosite crystals, very bright and with a characteristic brown color. From a mine little represented in collections.
Specimen very rich in prismatic epidote crystals, well defined, with an intense green color, transparent to translucent. These pieces came out in the late 1990s and are different from the usual ones for the locality. It was acquired by Peter Seroka from G. Gautier at the Munich Show in 2002.
Rübenkeller is the famous historical locality for chabazite and phillipsite from about 1850 and was very prolific in zeolite specimens in the late 19th century. In this specimen, from the Freiburg Bergakademie, we can see various aggregates of very well defined, pseudocubic, transparent and very bright crystals, which fill the vacuoles of the volcanic rock. It is accompanied by a very interesting old handwritten label.
These specimens come from an andesite quarry located in NE Hungary. This quarry is worked by Colas Északkő Co. In year 2013, hyaline beautiful specimens of opal were collected. In the quarry explosives are used to excavate the rocks, so most of the specimes dissapears. From summer 2015 access is not permitted, but some specimens were collected before... These facts make it difficult to see good samples of this quality.
Hyalite opal (opal-AN) aggregates (crown shaped) are completely transparent, like drops of water, with an exceptional brightness. They are highly fluorescent under shortwave UV and also under longwave. Sometimes they accompanied by globular aggregates of calcite-aragonite. They are disposed very aerial on a porous matrix of andesite.