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RM593   Betafite (of Hogarth 1977), variety of Pyrochlore

Ambatoasana, Soavinandriana, Itasy, Antananarivo, Madagascar

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 P. Sainfeld, mineralogist at the École des Mines de Paris.
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: 5,6 x 4,0 x 3,6 cm.
Found in 1960's.

Ex-col. Sainfeld (École Mines Paris).
Presents radioactive activity.


 

RM592   Betafite (of Hogarth 1977), variety of Pyrochlore

Ambatofotsy pegmatite, Mahavelona, Soavinandriana, Antananarivo, Madagascar

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 P. Sainfeld, mineralogist at the École des Mines de Paris.
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: 5,5 x 4,5 x 4,3 cm.
Main crystal: 4,3 x 4,0 cm.
Found in 1960's.

Ex-col. Sainfeld (École Mines Paris).
Presents radioactive activity.
 

RM1079   Elbaite-Liddicoatite with londonite and feldpar

Ambalabe pegmatite, Manapa pegmatite Field, Betafo, Vakinankaratra, Antananarivo, Madagascar

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.

 

RM738   Euxenite-(Y)

Ambatofotsikely pegmatite, Betafo, Vakinankaratra, Antananarivo, Madagascar

Euxenite-(Y) is an uncommon oxyde of niobium with tantalum and titanium and Rare Earth Elements (REE), with some calcium and radioactive elements like uranium or thorium. These elements give it a radioactive activity. This specimen we offer you is a cluster of parallel growth crystals, well-formed, with a chisel termination.With the classic ocher patina. A good chance to get this rare species.


Size: 3,5 x 2,0 x 1,4 cm.

Desc./ Unkn. Col. Nr. 444.
Presents radioactive activity.


 

RM1403   Euxenite-(Y)

Samiresy, Tritriva Commune, Betafo, Vakinankaratra, Antananarivo, Madagascar

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.
 

RM1194   Microcline var. amazonite

Imalo, Andrembesoa, Betafo, Vakinankaratra, Antananarivo, Madagascar

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.

 

RM1833   Quartz with fuchsite inclusions

Ihovitra, Itremo massif, Ambatofinandrahana, Amoron'i Mania, Fianarantsoa, Madagascar

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)
 

RM1080   CORUNDUM (var. RUBY) en MUSCOVITE

Zazafotsy Quarry (Amboarohy), Zazafotsy, Horombe, Fianarantsoa, Madagascar

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
 

RM1825   Thorianite

Amboasary Sud District, Anosy, Tuléar, Madagascar

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.


 

RM1834   Almandine-Spessartine

Ialamitana Pegmatites, Sahanivotry Manandona, Antsirabe II, Vakinankaratra, Madagascar

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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