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RM3203   Quartz cepter with petroleum and bitumen inclusions
SiO₂
  -  4. Oxides and hydroxides

Interesting scepter quartz crystals with several inclusions of "petroleum" and other hydrocarbons. The petroleum in these quartz crystals from Madagascar appear brownish yellow and, as with many other petroleum inclusions in quartz, they react to long and short wave UV light with yellow to blue fluorescence. Microscopic examination reveals numerous complex fluid inclusions containing obvious brownish yellow petroleum, gas bubbles presumed to be methane, dark solids of what is likely asphaltite, and a colorless immiscible liquid that could be probably water. Microscopic inclusions in quartz are of particular interest to the collector due to their spectacular UV reaction (gia.edu).

Size: 3.7 x 2.2 x 1.5 cm.
Found in ±2022.
Fluorescent under LW-UV and SW-UV lights
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RM3202   Quartz cepter with petroleum and bitumen inclusions
SiO₂
  -  4. Oxides and hydroxides

Interesting scepter quartz crystals with several inclusions of "petroleum" and other hydrocarbons. The petroleum in these quartz crystals from Madagascar appear brownish yellow and, as with many other petroleum inclusions in quartz, they react to long and short wave UV light with yellow to blue fluorescence. Microscopic examination reveals numerous complex fluid inclusions containing obvious brownish yellow petroleum, gas bubbles presumed to be methane, dark solids of what is likely asphaltite, and a colorless immiscible liquid that could be probably water. Microscopic inclusions in quartz are of particular interest to the collector due to their spectacular UV reaction (gia.edu).

Size: 4.5 x 1.6 x 1.6 cm.
Found in ±2022.
Fluorescent under LW-UV and SW-UV lights
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RM3200   Grandidierite

Rich group of grandidierite crystals, on matrix. Unusually well defined and aerial for the species. Brilliant, translucent and with an intense uniform bluish-green color. We can observe prismatic crystals with terminal faces. A sample of great quality for this rare nesosilicate. With the label of the collector.
Grandidierite was discovered by the French mineralogist, Alfred Lacroix in 1902 and named after French explorer and naturalist Alfred Grandidier (1836-1912), who wrote the great natural history book: "L'Histoire physique, naturelle et politique de Madagascar". The first reported locality for the species is at the cliffs of Andrahomana, on the southern coast of Madagascar. The species is a magnesium, iron, aluminum borosilicate and although it has been found in multiple localities around the world, it's still considered exceptionally rare, especially in gem quality material (mindat).

Size: 7.4 x 4 x 3.5 cm.
Main crystal: 18 mm.
Found in ±1975.
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RM3227   Monazite-(Ce)
Ce(PO₄)
  -  8. Phosphates, arsenates and vanadates

Monazite-(Ce) crystal, floater, rich in faces, with luster and intense brown color. Nowadays finding specimens with this quality is not easy.
These specimens have been analyzed, indicating that cerium is predominant, and that it is accompanied by other REEs such as lanthanum and neodymium, together with thorium, which gives it some radioactivity. We will send the results and label to the buyer.

Size: 2.3 x 1.9 x 0.8 cm.
Presents radioactive activity ☢.
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RM3179   Monazite-(Ce) and Columbite-Tantalite
Ce(PO₄)
  -  8. Phosphates, arsenates and vanadates

Very good monazite-(Ce) crystal, floater, rich in faces, with luster and light brown color. It is accompanied by a cubic crystal of columbite-tantalite embeded in. These specimens have been analyzed, indicating that cerium is predominant, and that it is accompanied by other REEs such as lanthanum and neodymium, together with thorium, which gives it some radioactivity. We will send the results and label to the buyer.

Size: 4.1 x 2.9 x 1.2 cm.
Presents radioactive activity ☢.
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RM3178   Monazite-(Ce)
Ce(PO₄)
  -  8. Phosphates, arsenates and vanadates

Excellent monazite-(Ce) crystal, totally floater, rich in faces, with luster and intense brown color. Nowadays finding specimens with this quality is not easy.
These specimens have been analyzed, indicating that cerium is predominant, and that it is accompanied by other REEs such as lanthanum and neodymium, together with thorium, which gives it some radioactivity. We will send the results and label to the buyer.

Size: 4.3 x 2.5 x 1.1 cm.
Presents radioactive activity ☢.
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RM2720   Hambergite

Hambergite is a rare mineral species, a beryllium hydroxyborate, which occurs in the tourmaline pegmatites of Anjanabonoina. This sample shows us a group of crystals of exceptional size and quality, flattened and with well-defined terminations. Transparent to translucent, with brilliance. This mineral is usually found as single crystals, rarely on matrix, and less with this size. A museum piece.

Size: 7.2 x 5.2 x 4 cm.
Main crystal: 3.7 cm.
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RM2795   Betafite (of Hogarth 1977), pyrochlore supergroup

A huge size crystal of betafite showing defined octahedral faces (triangular) and developed dodecahedral ones. Very interesting for its crystallography and species. An oldie, classic and representative for the species.
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: 4.8 x 4.4 x 4.1 cm.
Found in ±1995.
Presents radioactive activity ☢.
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RM2522   Quartz
SiO₂
  -  4. Oxides and hydroxides

Group of hyaline quartz crystals, very transparent, brilliant, with complex shapes due to polycrystalline and window growths. With orange inclusions. Very aesthetic and interesting specimens from a new Malagasy locality.

Size: 4.8 x 4.2 x 2.2 cm.
Found in 2018.
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RM2523   Scepter quartz
SiO₂
  -  4. Oxides and hydroxides

Curious parallel growth of quartz crystals in scepter. A very aesthetic miniature of a new locality in Madagascar.

Size: 3 x 1.5 x 1 cm.
Found in 2018.
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RM2521   Scepter quartz
SiO₂
  -  4. Oxides and hydroxides

Group of hyaline quartz crystals, very brilliant, one of them more developed and showing the scepter growth stands out. With polycrystalline growths. An aesthetic novelty from Madagascar.

Size: 3.8 x 2.7 x 1.8 cm.
Main crystal: 2.7 cm.
Found in 2018.
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RM2520   Quartz
SiO₂
  -  4. Oxides and hydroxides

Aesthetic quartz specimen, very transparent and with orange inclusions. It shows a very curious window growths and some facets of the rhombohedron. These specimens come from a little-known locality. Really interesting.

Size: 4.3 x 3 x 1.9 cm.
Found in 2018.
45 €
RM2519   Doubly terminated quartz
SiO₂
  -  4. Oxides and hydroxides

Group of doubly terminated quartz crystals, very transparent and with orange inclusions. With prisms and terminal faces with very evident polycrystalline and window growths. These specimens come from a new not well-known locality. Very aesthetic and pure brilliance.

Size: 5.7 x 5.2 x 2.6 cm
Main crystal: 5.7 cm.
Found in 2018.
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RM2503   Fluorite
CaF₂
  -  3. Halides

A good size specimen showing a group of cubic fluorite crystals, between translucent and transparent, with an intense green color with delicate dichroism under sunlight. The crystals are interpenetrated and show geometric color zoning and interesting and esthetic inclusions of white color. Very fluorescent under LW-UV and SW-UV. New locality for fluorite in Madagascar.

Size: 12 x 9.5 x 7 cm.
Main crystal: 3.6 cm.
Found in 2018.
Fluorescent under LW-UV and SW-UV lights
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RM2502   Fluorite
CaF₂
  -  3. Halides

A good size specimen showing a group of cubic fluorite crystals, between translucent and transparent, with an intense green color with delicate dichroism under sunlight. The crystals are interpenetrated and show geometric color zoning and interesting and esthetic inclusions of white color. Very fluorescent under LW-UV and SW-UV. New locality for fluorite in Madagascar.

Size: 15.5 x 7.7 x 6.8 cm.
Main crystal: 2.2 cm.
Found in 2018.
Fluorescent under LW-UV and SW-UV lights
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RM2200   Fluorite
CaF₂
  -  3. Halides

Group of cubic fluorite crystals, between translucent and transparent, with a deep green color with delicate dichroism under sunlight. The crystals are interpenetrated and showing geometric color and inclusions zoning. Very fluorescent under LW-UV and SW-UV. New locality/area for fluorite from Madagascar.

Size: 10 x 4.6 x 3.4 cm.
Main crystal: 2.3 cm.
Found in 2018.
Fluorescent under LW-UV and SW-UV lights
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RM2199   Fluorite
CaF₂
  -  3. Halides

Group of cubic fluorite crystals, between translucent and transparent, with a deep green color with delicate dichroism under sunlight. The crystals are interpenetrated and showing geometric color and inclusions zoning. Very fluorescent under LW-UV and SW-UV. New locality/area for fluorite from Madagascar.

Size: 8.6 x 6.9 x 5.2 cm.
Main crystal: 3 cm.
Found in 2018.
Fluorescent under LW-UV and SW-UV lights
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RM2107   Betafite (of Hogarth 1977), pyrochlore supergroup

A huge size crystal of betafite showing defined octahedral faces (triangular) and developed dodecahedral ones. Very interesting for its crystallography and species. An oldie, classic and representative for the species. This specimen belonged to the collection of Peraud-Pregilbert (France).
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: 2.8 x 2.5 x 2.2 cm.
Found in 1960's.
Presents radioactive activity ☢.
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RM1834   Almandine-Spessartine

Very sharp almandine-spessartine crystal from Madagascar pegmatites. Rich in faces, a textbook specimen. Under the light you can see transparencies of reddish tones, in fact it is of intense red. It is disposed very aerial on the matrix with feldspar and quartz. Complete, perfect, of a considerable size... The garnets from Ialamitana, has been found to be an intermediate almandine-spessartine (Mineralogical Record, 29, p. 132). A great piece for garnet group lovers.

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RM1833   Quartz with fuchsite inclusions
SiO₂
  -  4. Oxides and hydroxides

Very well developed prismatic colorless transparent crystals of quartz showing phantom geometrical inclusions. These inclusions of pale green fuchsite crystals takes well defined forms. Crystals are free of damage. Very interesting specimen.

Size: 5.1 x 4.6 x 4.5 cm.
Main crystal: 3.8 x 1.4 cm.
Found in 2013
Col. C. Manresa (Balaguer)
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RM1825   Thorianite
ThO₂
  -  4. Oxides and hydroxides

From a classic locality for the species is coming this thorianite cube, with pointed faces of the octahedron, intense black color and brightness. The thorianite is a thorium oxide, almost always with some uranium content, the uranothorianite variety. This specimen contains about 5-6% by weight of uranium. We will send the analysis to the buyer.

Size: 4 x 4 x 3 mm.
Found in 1998.
Presents radioactive activity ☢.
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RM1403   Euxenite-(Y)
(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)₂O₆
  -  4. Oxides and hydroxides

An old specimen collected in the 50s by L. Gautron in the pegmatite dikes those are located about 20 km SW of the city of Antsirabé, in the main highland of Madagascar. It is a euxenite-(Y) crystal showing defined faces and rounded edges, with good size. A historical specimen.

Size: 3.4 x 2.0 x 1.5 cm.
Found in ±1950.
Excol. L. Gautron.
Presents radioactive activity ☢.
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RM1194   Microcline var. amazonite
K(AlSi₃O₈)
  -  9. Silicates

Group of microcline crystals, amazonite variety, showing defined faces. They are embedded in a matrix of feldspar and smoky quartz. The color is good and very attractive.

Size: 8.6 x 4.0 x 4.0 cm
Main crystal: 17 x 16 mm.
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RM1079   Elbaite-Liddicoatite with londonite and feldpar

Sized elbaite-liddicoatite crystal, well defined, very aerial disposed, intense bourdeos red color, visible on the transparencies. It shows a striated prism faces with defines rhombohedral top faces. It shows a small dent that does not affect the aesthetics. On a feldspar matrix with sharp londonite crystals.

Size: 5.3 x 3.7 x 2.8 cm.
Main crystal: 37 x 26 mm.
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RM1080   CORUNDUM (var. RUBY) en MUSCOVITE

These specimens are labeled as corundum sapphire and ruby. They show a dual range of tones, between red to blue and purple, depending on the incident light and even within the same crystal. They have a very good quality and brilliance that makes them stand out from other of the same species. Crystals, which are doubly terminated, show the hexagonal prism, more or less elongated, and flattened pinacoidal terminal faces, sometimes with echeloned rhombohedral faces. On some faces we can observe geometric striated lines. They are disposed on a matrix of brilliant mica (muscovite) and feldspar.

Size: 4.5 x 4.5 x 2.8 cm.
Main crystal: 11 x 9 mm.
Fluorescent under LW-UV and SW-UV lights
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