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RM2826   Columbite-(Mn), columbite-tantalite series

Etiro pegmatites, Etiro Farm 50, Karibib, Erongo, Namibia

A good size crystal of columbite-(Mn) that shows parallel growths on the faces, with striations, intense luster and black color. The accompanying handwritten label indicates that it belongs from the Etiro pegmatites, in Namíbia, a locality of which few specimens have been seen in the market. The piece belongss from H.G. Hoppert. Sample has been analyzed and the results, as can be seen in the attached documents, indicate it contains more Mn than Fe, a columbite, but with values of Nb-Ta in the border area with tantalite domain. All results will be sent to the buyer.

Size: 4.8 x 3.8 x 1.7 cm.
Found in ±1970.

Col. H.G. Hoppert.
Analyzed specimen with report

Price: 240 €Buy

RM2111   Cheralite - Grayite, Brockite

Brabant Farm 168, Karibib, Erongo, Namibia

These specimens show yellowish nodules included in a feldspar matrix. First SEM-EDS analysis have yielded a phosphate of Th and Ca, with minor Pb. XRD has shown patterns of "bravantite", the old name for cheralite and brockite. The chemical base formula for these species are: grayite (Th,Pb,Ca)(PO4)·H2O; cheralite CaTh(PO4)2; brockite (Ca,Th,Ce)(PO4)·H2O. REE has not been found in EDS.
We could say that this yellow nodules belongs from altered monazite, formed by mixed species cheralite-grayite, with minor brockite. Accompanied in matrix by meta-autunite. We will send the full report.

Size: 5.3 × 3.7 × 3 cm.

Analyzed specimen with report


RM1455   Boltwoodite with calcite

Goanikontes Claim, Goanikontes, Swakopmund, Erongo, Namibia

A elongated vug lined with small calcite crystals on which are scatterd some radial clusters of acicular yellow to orange crystals of boltwoodite. This specimen is labeled as Rössing mine but during many years excellent boltwoodite samples were labeled as "Rössing" and thus confused with the Rössing Uranium mine in the area (which never produced any boltwoodite specimens). The correct locality is Goanikontes, a uranium claim 4 km SE of Goanikontes and 27 km E of Swakopmund, at a distance of 40 km from the Rössing Uranium Mine.

Size: 5.3 x 4.3 x 3.0 cm.
Main crystal: 4 mm.
Found in 1990's

Fluorescent under long wave UV

RM852   Smoky Scepter Quartz

Goboboseb Mts., Brandberg area, Erongo, Namibia

A scepter quartz crystal with smoky tones, transparence and brilliance. With window growths on rhombohedral faces. Very aesthetic.

Size: 6.8 x 3.7 x 3.4 cm.


RM780   Beryl (var. aquamarine) with smoky quartz, schorl and feldspar

Erongo Mts., Erongo, Namibia

Exceptional specimen of beryl, variety aquamarine, very aerial disposed on a matrix rich in developed smoky quartz crystals. Beryl shows very good transparency and blue color. Accompanied by another beryl doubly terminated in smoky quartz. Also with black schorl crystals and feldspar. The crystal has a small dent, but a very aesthetic piece.

Size: 9,5 x 9,0 x 3,7 cm.
Main crystal: 19 x 8 mm.