Excellent specimen of rhodochrosite from this classic American locality from where not many specimens are available, unless they appear in former collections. This piece entered the Joan Astor collection in 1976 and was acquired from Joan Montal, a well-known old dealer from Vilafranca del Penedés (Barcelona). Several rhombohedral rhodo crystals, very well defined, with a very aesthetic pink color. With a globular aggregate of a second generation of rhodo. It stands out on the matrix of quartz crystals. A unique piece.

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Excellent, sculptural, two-sided baryte "rose" from Oklahoma. Oxidized sand grains are included in the baryte crystal structure with colorful effect. Essentially a floater. The hole adds much aesthetics. Baryte was precipitated in interconnected voids in the rock, probably from barium-rich marine waters that covered the Permian Garber Sandstone during or shortly after its deposition about 250 million years ago. The rose-like concretions incorporated the iron-stained quartz sand grains and thus acquired the red color of the host Garber Sandstone (online). These are the official Oklahoma State Rock.
Very interesting article in Mineralogical Record July-August 2008.

Excellent, sculptural, two-sided baryte "rose" from Oklahoma. Oxidized sand grains are included in the baryte crystal structure with colorful effect. Essentially a floater. The hole adds much aesthetics. Baryte was precipitated in interconnected voids in the rock, probably from barium-rich marine waters that covered the Permian Garber Sandstone during or shortly after its deposition about 250 million years ago. The rose-like concretions incorporated the iron-stained quartz sand grains and thus acquired the red color of the host Garber Sandstone (online). These are the official Oklahoma State Rock.
Very interesting article in Mineralogical Record July-August 2008.

For uranium mineral collectors, this carnotite of an intense yellow color, formed by numerous globular aggregates of crystals, covering the surface of the sandstone matrix. An American classic, labeled E. Kucera (Barcelona).

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Rich specimen formed by numerous spinel crystals showing octahedral form, black colour, very brilliant and well defined faces and edges. Sample is accompanied by the label of Douglas "Doug" Toland, with notes those indicates it could be gahnite or chromite, but the semi-quantitative analysis done with SEM-EDS microscopy shows that it is spinel, not identified in the mine before. It is accompanied by probably grossular and chlorite. A good specimen for the species and for this cold locality.

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Bunker Hill pyromorphite specimens are among the most appreciated by collectors worldwide. This specimen shows a druse of barrel-shaped crystals with an excellent color and brightness, some of them doubly terminated and with a good size. It is increasingly difficult to find samples of this quality at a reasonable price.

Very aesthetic specimen of kinoite from this famous American mine. It is a druse formed by small crystals of this rare silicate of calcium and copper, very characteristic of this mine, which are partially covered by brilliant and transparent crystals of Hydroxyapophyllite-(K). We also observe the kinoite as darker globular aggregates. Pure aesthetics and brightness. The best kinoites came out for a short time in the 70s from this Arizona mine, and specimens show up only rarely on the market.

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Johannsenite is a rare calcium and manganese silicate of the pyroxene group. In this specimen it appears forming aggregates of sharp prisms, with dark green color, accompanied by tabular lanceolate crystals of axinite-(Mn) of greenish tones and quartz crystals. A good-sized specimen of an unusual species.

A very esthetic and good size specimen formed by several globular aggregates of acicular crystals of rosasite, of bluish green color, some partially covered by bright and transparent calcite crystals. It is accompanied by smithsonite and in a goethite matrix.

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Agatized coral with marked bands. In a very visible coral matrix. Filled inside with botryoidal and banded chalcedony. The sparkly, translucent botryoids and banding have a pleasing variety of honey-brown and creamy colors. Very aesthetic and unusual in the marked. Fluoresces in a light-blue color under a long wave fluorescent light.

Aesthetic cluster of greenish andradite crystals, very well defined, bright and slightly iridescent. From Stanley Butte, Arizona, classic locality for these specimens. No damage to any of the main crystals.

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On a sandstone matrix some yellow crusts of coconinoite formed by small tabular to micaceous crystals. This sample has been analyzed by SEM-EDS and we will send the results to the buyer.

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This specimen of good size and quality comes from a classic North American locality for the species. Numerous pink crystals of inesite coat the interior of a vug in the matrix. Crystals of inesite are very sharp and brilliant. A good piece of this ancientlocality.

Topaz crystal aesthetically disposed on a rhyolite matrix. It shows several faces very well defined, with an excellent transparency and a uniform tone. From a classic locality.

Wavellite specimens from Arkansas are becoming rare from this locality. In this remarkable sample we can see globular aggregates of crystals of this phosphate, with a second generation that covers them partially and of a lighter green color. Good color and aesthetics. A real classic.

Good sized group of rutile crystals from this classic North American locality for the species. They show very defined facets, excellent brilliance, with transparencies and reddish reflections. With forms of contact with the matrix and other accompanying crystals. An opportunity to get a historical piece.

Groups of topaz crystals aesthetically disposed on a rhyolite matrix. Some of them isolated and very rich in faces. They show very well defined faces and edges, with an excellent transparency and a uniform tone. From a classic locality.

A very aesthetic cluster of prismatic, lustrous and gemmy, ice-blue baryte crystals with minor calcite from the named Leeson Pocket at the famous Stoneham locality of Colorado. The form is excellent and the largest crystals are doubly terminated. This fine piece is from the major 1989 finds and purchased to E. Kucera (Barcelona). Nearly pristine, only one crystal on the periphery is broken. An excellent specimen, uncommon in the market. A really interesting article in Rocks and Minerals available here.

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Very esthetic aggregates of tabular tyuyamunite crystals. Very bright, intense yellow greenish color and contrasting with the matrix. A very representative specimen for the species.

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This specimen is an awaruite nugget, rounded by the fluvial action. The awaruite, formerly known as "josephinite" by this North American locality, is a natural alloy of iron and nickel, with compositions within the Ni3Fe-Ni2Fe range (Ni3Fe is more common). Many people mistakenly believe that "josephinites" are of meteoritic origin, but in fact the awaruite is extremely rare in metallic meteorites. The placer deposits of this area were discovered and exploited in the middle of the XIXth century. The awaruite of this deposit is usually accompanied by serpentine, andradite and orcelite: Ni5-xAs2 (x = 0.23).

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Callaghanite is an very rare copper magnesium carbonate, known from only a few localities worldwide. This specimen has bright royal-blue microcrystals and hails from the Type Locality in Nevada. Good size and rich sample.

The extremely glassy, transparent to translucent opal colors range from colorless to very rich orange. A really excellent, sculptural and rich bi-colored large matrix opal example from this locality. Bright neon-green fluorescence. Very old material. Matrix opal specimens of this large size are rare from this Oregon locality.

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Rich group of microcline crystals, amazonite variety, showing defined faces and edges and a very aerial disposition. The color is quite good and very attractive. From an old Catalan collection.

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Agatized coral with marked bands. In a very visible coral matrix. Filled inside with botryoidal and banded chalcedony. The sparkly, translucent botryoids and banding have a pleasing variety of honey-brown and creamy colors. Very aesthetic and unusual in the marked. Fluoresces in a light-blue color under a long wave fluorescent light.

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Curious specimen of turquoise, authentic turquoise, of a slightly greenish blue color, forming globular and elongated nucleus, in a matrix of goethite with other phosphates as possibly strengite. It is slightly polished which allows us to see perfectly the forms that the phosphate takes inside the matrix.

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