Strüverite is a variety of rutile rich in tantalum and iron, with the formula (Ti,Ta,Fe)O₂, with variable proportions of niobium (Nb). When the proportion of Ta>Nb is called strüverite, but if Nb≥Ta the variety has been named ilmenorutile. The specimens from this locality in Madagascar have been mainly determined to be of the Ta-rich variety: strüverite. An interesting specimen with a very special chemistry.

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Good size garnet crystal belonging to the almandine-spessartine series, usually with a predominance of the first one. The analyzes indicate the presence of Fe and Mn, with traces of Mg. These specimens were identified as pyrope (magnesium aluminosilicate), but the analytical results do not indicate this.

50 €

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Group of garnet crystals belonging to the almandine-spessartine series, usually with a predominance of the first one. The analyzes indicate the presence of Fe and Mn, with traces of Mg. These specimens were identified as pyrope (magnesium aluminosilicate), but the analytical results do not indicate this.

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Group of garnet crystals belonging to the almandine-spessartine series, usually with a predominance of the first one. The analyzes indicate the presence of Fe and Mn, with traces of Mg. These specimens were identified as pyrope (magnesium aluminosilicate), but the analytical results do not indicate this.

45 €

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Group of garnet crystals belonging to the almandine-spessartine series, usually with a predominance of the first one. The analyzes indicate the presence of Fe and Mn, with traces of Mg. These specimens were identified as pyrope (magnesium aluminosilicate), but the analytical results do not indicate this.

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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.

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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.

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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.

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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.

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.

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.

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.

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.

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.

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