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RM2138   Boracite, Hilgardite and magnesite
Mg3B7O13Cl

Specimens of boracite from this English mine show a pale bluish tone, with complex forms of the tetrahedron, modified by the cube and the dodecahedron, and stepped growths. Between transparent to translucent. They are accompanied by colorless hexagonal tabular crystals of magnesite and aggregates of reddish-colored hilgardite crystals. Boracite shows reddish hues due to hilgardite inclusions.Both boracite and hilgardite, are magnesium and calcium chloroborates respectively. This mine, which is located east of Loftus, near Easington, is worked to obtain sodium and potassium salts. When miners find veins of these borates, the rock becomes very hard, which is a problem for exploitation and a joy for collectors. This English mineral classics are not usual in the market. 1t4j20

Size: 7.8 x 5.2 x 3.5 cm.
Main crystal: 4 mm.
Classic locality
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RM2101   Boracite, Hilgardite and magnesite
Mg3B7O13Cl

Specimens of boracite from this English mine show a pale bluish tone, with complex forms of the tetrahedron, modified by the cube and the dodecahedron, and stepped growths. Between transparent to translucent. They are accompanied by colorless hexagonal tabular crystals of magnesite and aggregates of reddish-colored hilgardite crystals. Boracite shows reddish hues due to hilgardite inclusions.
Both boracite and hilgardite, are magnesium and calcium chloroborates respectively. This mine, which is located east of Loftus, near Easington, is worked to obtain sodium and potassium salts. When miners find veins of these borates, the rock becomes very hard, which is a problem for exploitation and a joy for collectors. This English mineral classics are not usual in the market.

Size: 7.5 x 6 x 2.4 cm.
Main crystal: 3 mm.
Classic locality
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RM2100   Boracite, Hilgardite and magnesite
Mg3B7O13Cl

Specimens of boracite from this English mine show a pale bluish tone, with complex forms of the tetrahedron, modified by the cube and the dodecahedron, and stepped growths. Between transparent to translucent. They are accompanied by colorless hexagonal tabular crystals of magnesite and aggregates of reddish-colored hilgardite crystals. Boracite shows reddish hues due to hilgardite inclusions.
Both boracite and hilgardite, are magnesium and calcium chloroborates respectively. This mine, which is located east of Loftus, near Easington, is worked to obtain sodium and potassium salts. When miners find veins of these borates, the rock becomes very hard, which is a problem for exploitation and a joy for collectors. This English mineral classics are not usual in the market.

Size: 8.4 x 5.2 x 2 cm.
Main crystal: 2 mm.
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RM2119   Fluorapatite

On a calcite and quartz matrix sits an aesthetic, doubly terminated fluorapatite crystal with this nice blue color, with curious rounded faces and edges. The very glassy luster, translucent, color and size of this specimen make this a fine mineral specimen. This Russian fluorapatite specimens from this locality are highly appreciated for lustre and gemminess. Good size and very aerial disposed.

Size: 4.8 x 4.2 x 3.5 cm.
Main crystal: 4.5 x 2.2 cm.
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RM2115   Pyrolusite

Very aesthetic stalactite of goethite totally covered with sharp lanceolated pyrolusite crystals, disposed in a very aerial shape, with an intense luster, colour between metallic gray to almost black. A notable specimen for the species and the locality.

Size: 6.8 x 3.5 x 2 cm.
Main crystal: 3 mm.
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RM2118   Rhodochrosite

Druse of elongated scalenohedral rhodochrosite crystals, with flattened rhombohedral terminations. They have an intense colour, brilliance, transparent to translucent. On a matrix of manganese oxides. A classic and lost locality from which it is currently very difficult to obtain samples like this that came out in the 1970s and early 1980s and no more has been found.

Size: 5.4 x 4.7 x 3.2 cm.
Main crystal: 6 mm.
Found in ±1980.
Classic locality
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RM2117   Rhodochrosite

Druse of elongated scalenohedral rhodochrosite crystals, with flattened rhombohedral terminations. They have an intense colour, brilliance, transparent to translucent. On a matrix of manganese oxides. A classic and lost locality from which it is currently very difficult to obtain samples like this that came out in the 1970s and early 1980s and no more has been found. With old label.

Size: 6.5 x 5.2 x 3.8 cm.
Main crystal: 6 mm.
Found in ±1980.
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RM2116   Rhodochrosite

Druse of very elongated scalenohedral rhodochrosite crystals, with flattened rhombohedral terminations. They have an intense colour, brilliance, transparent to translucent. On a matrix of manganese oxides. A classic and lost locality from which it is currently very difficult to obtain good size samples like this that came out in the 1970s and early 1980s and no more has been found. With old label.

Size: 11.4 x 10.2 x 5.3 cm.
Main crystal: 3 mm.
Found in ±1980.
Classic locality
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RM2120   Bournonite with pyrite, galena
CuPbSbS3

Very aesthetic specimen formed by numerous bournonite crystals, excellent luster, sharps and cyclically twinned. They are accompanied by cube octahedral galena crystals with rounded faces and edges and brilliant pyrite. Nice miniature.

Size: 4.5 x 3.6 x 2.4 cm.
Main crystal: 8 mm.
Found in 2019.
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RM2121   Bournonite with pyrite, sphalerite
CuPbSbS3

In a matrix formed by octahedral pyrite crystals, very bright and faceted, various groups of sphalerite crystals are disposed on which the bournonite cyclic twins stand out. They are accompanied by small quartz crystals and hydrozincite globules. A very aesthetic piece.

Size: 5.2 x 3.8 x 3.2 cm.
Main crystal: 6 mm.
Found in 2019.
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RM2145   Vanadinite on goethite

Curious specimens of vanadinite showing yellow, slightly orange, hexagonal prismatic crystals, on which a thin layer of goethite has been deposited. At the same time, on this layer another generation of vanadinite and calcium-rich pyromorphite (phosphohedyphane), such as the attached analyzes show, we will send to the buyer. They are disposed on a matrix of goethite. Very interesting and different specimen from this classic Moroccan mine. Take a look to the SEM image of second generation crystals with an unusually rich facet...

Size: 8.5 x 7.5 x 3.8 cm.
Main crystal: 1.2 cm.
Found in 2019.
Analyzed specimen with report
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RM2094   Malachite

Very aesthetic specimen that shows globular aggregates of malachite, very bright and intense green. Also as velvety botryoidal aggregates. If you take a look under the magnifying glass, you will see that they are formed by several small crystals of this copper carbonate, transparent and defined. From this classic Congolese locality for the species.

Size: 10.5 x 7 x 5.4 cm.
Classic locality
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RM2135   Malachite

Very aesthetic specimen that shows globular aggregates of malachite, very bright and intense green. If you take a look under the magnifying glass, you will see that they are formed by several small crystals of this copper carbonate, transparent and defined. From this classic Congolese locality for the species.

Size: 6.8 x 5.7 x 4.5 cm.
Classic locality
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RM2136   Malachite

Very aesthetic stalactite of malachite, with an intense green color and a very aerial layout. Good size. From this classic Congolese locality for the species.

Size: 9.5 x 2.8 x 2.7 cm.
Classic locality
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RM2139   Picropharmacolite, Pharmacolite, Erythrite

Very rich specimen formed by several white (transparent) acicular crystals of picropharmacolite and pharmacolite, accompanied by velvety pinkish Mg-rich erythrite mixed with them. Some sinfeldite crystala ggregates are present. On a nickelskutterudite matrix. Collected in Bou Azer mine in february 2018. Analyzed by SEM-EDS.

Size: 7.8 x 6.8 x 5.5 cm.
Found in 02/2018.
Analyzed specimen with report
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RM2140   Picropharmacolite, Pharmacolite, Erythrite

Very rich specimen formed by several white (transparent) acicular crystals of picropharmacolite and pharmacolite, accompanied by velvety pinkish Mg-rich erythrite mixed with them. Some sinfeldite crystala ggregates are present. On a nickelskutterudite matrix. Collected in Bou Azer mine in february 2018. Analyzed by SEM-EDS.

Size: 6.8 x 6.7 x 3.5 cm.
Found in 02/2018.
Analyzed specimen with report
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RM2143   Gold, variety electrum

Aggregate of gold crystals, electrum variety, with luster, intense color and from a locality not well represented in collections. They come from a mining area that began to be worked at the beginning of the 20th century for the extraction of gold and silver. We have analyzed some specimens and they show a silver content between 20% and 28% (%weight).

Size: 9 x 6 x 4 mm.
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RM2142   Gold, variety electrum

Skeletical to arborescent aggregate of gold crystals, electrum variety, with luster, intense color and from a locality not well represented in collections. They come from a mining area that began to be worked at the beginning of the 20th century for the extraction of gold and silver. We have analyzed some specimens and they show a silver content between 20% and 28% (%weight).

Size: 8 x 3 x 1 mm.
Analyzed specimen with report
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RM2141   Gold, variety electrum

Skeletical to arborescent aggregate of gold crystals, electrum variety, with luster, intense color and from a locality not well represented in collections. They come from a mining area that began to be worked at the beginning of the 20th century for the extraction of gold and silver. We have analyzed some specimens and they show a silver content between 20% and 28% (%weight).

Size: 7 x 3 x 1 mm.
Analyzed specimen with report
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RM2127   Smithsonite

Stalactitic to botryoidal aggregates of smithsonite of yellowish tone, partially covered by a second generation of the same species, colorless to white. This mine is located in the Magdalena concession, near Robriguero, with gallery and open pit works. The mine was worked until 1924 to obtain calamine and some galena. Nowadays it is very difficult to find samples.

Size: 6.2 x 6 x 5.2 cm.
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RM2113   Pyromorphite

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.

Size: 6 x 5.2 x 4.5 cm.
Main crystal: 5 mm.
Found in 1998.
Classic locality
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RM2114   Smithsonite and hemimorphite

Very aesthetic globular aggregates of smithsonite, with an apple green color, translucent, accompanied by several lanceolated sharp and transparent hemimorphitecrystals. In a vug of the goethite matrix. Smithsonite specimens from this Mexican mine are highly appreciated by collectors. From the 8th level of this mine.

Size: 8 x 6 x 4.5 cm.
Main crystal: 1.3 cm aggreg.
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RM2091   Cuprian dundasite

Dundasite is an unusual lead and aluminum hydroxycarbonate, which is formed as a secondary mineral in the oxidation zone of lead deposits. This Pyrenean locality is very interesting for its diverse paragenesis. In this specimen we observe under the magnifying glass numerous and aesthetic aggregates of dundasite as acicular crystals of silky luster, some slightly bluish due to their Cu content, contrasting on the matrix.

Size: 3.1 x 2.4 x 2.3 cm.
Found in 2018.
Analyzed specimen with report
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RM2090   Cuprian dundasite

Dundasite is a rare lead and aluminum hydroxycarbonate, which is formed as a secondary mineral in the oxidation zone of lead deposits. This Pyrenean locality is very interesting for its diverse paragenesis. In this specimen we observe under the magnifying glass numerous and aesthetic aggregates of dundasite as acicular crystals of silky luster, some slightly bluish due to their Cu content, contrasting on the matrix.

Size: 3.2 x 2.4 x 1.3 cm.
Found in 2018.
Analyzed specimen with report
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RM2089   Cuprian dundasite

Dundasite is an unusual lead and aluminum hydroxycarbonate, which is formed as a secondary mineral in the oxidation zone of lead deposits. This Pyrenean locality is very interesting for its diverse paragenesis. In this specimen we observe under the magnifying glass numerous and aesthetic aggregates of dundasite as acicular crystals of silky luster, some slightly bluish due to their Cu content, contrasting on the matrix.

Size: 2.5 x 1.8 x 1.4 cm.
Found in 2018.
Analyzed specimen with report
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