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RM2137   Betafite (of Hogarth 1977), variety of Pyrochlore

Group of interpenetrated betafite crystals of good size that show the most developed faces of the dodecahedron. Interesting crystallography. It is accompanied by zircon crystals. These mottled-brown isometric crystals are from the well-known Silver Crater Mine at Bancroft. This is an excellent and uncommon example, today. Most specimens of this quality came out in the 1950s, during the active mining period. An old, classic and essential piece in any collection. This specimen bears the label of Tysons', a Canadian mineral dealer.
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).

Size: 4 x 3 x 2.5 cm.
Main crystal: 2.4 x 2.4 cm
Presents radioactive activity.
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RM2098   Fluorapatite

Curious group of fluorapatite crystals, of intense green color, interpertered and with parallel growths. One side is crystalized, the other not... A curiosity analyzed since we doubted that it was not a diopside.

Size: 4 x 2.2 x 1.2 cm.
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RM2096   Clinochlore, seraphinite variety
Mg5Al(AlSi3O10)(OH)8

Aesthetic specimen of clinochlore, variety seraphinite, forming nodular masses of radiating crystals. Polished slabs such as this have become popular ornamental items. The varietal name seraphinite refers to Biblical angelic beings having three pairs of wings, and is a trade name referring to the fibrous, silvery crystals that compose it. One side is polished showing the internal structure; the other side is natural with this "curious" label...

Size: 7.2 x 4.8 x 1.5 cm.
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RM2097   Arsenatian Vanadinite
Pb₅(VO₄)₃Cl
  -  8. Phosphates, arsenates and vanadates

Rich group of sharp arsenical vanadinite crystals, with curved faces prisms, barrel-shaped and many of them doubly terminated, with the characteristic color of this variety. Two generations of crystals are observed, those of greater size opaque and with a brown tone, on which a second generation of transparent toasted honey tone crystals has grown, all very very brilliant. A pleasure under the magnifying glass. This mine is also known as Apex.

Size: 4.2 x 4 x 2.8 cm.
Main crystal: 9 mm.
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RM2099   Hematite
Fe₂O₃
  -  4. Oxides and hydroxides

Rich group of tabular hematite crystals, very brilliant and forming very aesthetic rosettes. Pepper by small quartz crystals. They are disposed on a matrix of solid hematite. This hematite mine is located southeast of Egremont and was operated from 1903 until its closure in 1973. This aesthetic piece comes from an unidentified German collection.

Size: 4.6 x 4.5 x 2.4 cm.
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RM2103   Hilgardite, Boracite and magnesite
Mg3B7O13Cl

Very rich hilgardite specimen showing a reddish-colored sharp crystals. They are covering a layer of boracite crystals, as a matrix. 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: 4 x 3.2 x 3 cm.
Classic locality
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RM2102   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: 5 x 4.6 x 4.4 cm.
Main crystal: 5 mm.
Classic locality
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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.

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
Pb₅(VO₄)₃Cl
  -  8. Phosphates, arsenates and vanadates

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
Cu₂(CO₃)(OH)₂
  -  5. Carbonides and nitrates

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
Cu₂(CO₃)(OH)₂
  -  5. Carbonides and nitrates

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
Cu₂(CO₃)(OH)₂
  -  5. Carbonides and nitrates

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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