FMF - Friends of Minerals Forum, discussion and message board

[Roger Warin]

About the copper-bearing crescent, referred to as the South Katanga geological scandal.
Mining centers: Shinkolobwe (U), Lubumbashi (Cu), Likasi (Cu), Kambove (Cu, Co.), Kipushi (Zn, Cu, Ge).

[Roger Warin]

Selenian barite

[Roger Warin]

Dewindtite - hydrated phosphate of uranyl and lead.
yellow canary tablets.
No fluorescence.

[Roger Warin]

Pseudomalachite: Cu5(PO4)2(OH)4 on chrysocolla, Mashamba, Katanga.
Monoclinic crystals of pseudomalachite are very rare in Congo.
The macrophoto shows well the hillocky appearance, dark green to dark gray.

Under the microscope, the fine texture appears.
Aggregates of acicular crystals, reflective laterally.
Gray tint. Some parts, whose green colored ends, would correspond to late elongation or secondary growth of pseudomalachite microcrystals.

[Roger Warin]

Liege Intermineral Expo 4-5 November 2017.

A nice exhibition was in Liège (Belgium), Palais des Congrès, along the river "Meuse". 4 institutions or collectors participated:
National Museum of Natural History of Luxembourg, Dr. Simon Philippo.
Laboratory of Mineralogy - University of Liege, Prof. Frédéric Hatert.
Francis Coune and Valère Berlage.
Rare and nice specimens were presented.

Since the theme was Congo, I will place the photos of the specimens in the post "Minerals of D.R. Congo.”

[Roger Warin]

National Museum of Natural History of Luxembourg

[Roger Warin]

National Museum of Natural History of Luxembourg

[Roger Warin]

Professor of Geology Paul FOURMARIER (1877-1970)-
University of Liège, inventor of microtectonics.
(bronze plate).

Fourmarierite and some minerals

[Roger Warin]

MNHN Luxembourg

[Roger Warin]

Kamotoite, Kamoto East Open cut, Kolwezi, Katanga.

Relatively recent mineral, described in 1986 (Deliens and Piret).
Kamotoite-(Y) = Y2(UO2)4(CO3)3O4.14H2O
Hydrated Carbonate of Uranyl and Rare Earth.
Transparent slats of lemon yellow color. Tip termination, 35 ° angle.
Dehydrated, the kamotoite becomes opaque.

[Roger Warin]

It may be useful to locate mines on a map of Kolwezi area, Katanga.

[Roger Warin]

Hello,

It's time to show you some rarities from Katanga (Shinkolobwe).
The first specimen is 1 cm wide.
We find on a background of poorly crystallized torbernite, tan needles of dumontite, red curite and geld curienite. FOV = 3 mm.
This is the only sample on which the curienite was analyzed in Katanga. This mineral is normally found in Mounana, Franceville (Gabon).

[Roger Warin]

Another aspect of curienite. Crystals are never seen in Mounana mine.

[Roger Warin]

Hi,
Here the expansion of the torbernites area. The elongation of the torbernite crystals is rather unusual. This habitus is found at Shinkolobwe.
The saleeiteite can carry in Shinkolobwe an epitaxy of torbernite, but on this sample, these crystals are too small to be discerned. The sample size was too big for a larger magnification.
Note the unusual elongated prismatic crystallization of the torbernite crystals.

[Roger Warin]

Hi,
About epitaxy.
Another sample of saleeite / torbernite was photographed in 2015. I add some photos showing the epitaxy of the torbernite on the saleeite.
From Dal Bo Fabrice’s thesis (Mineralogy and crystal chemistry of natural and synthetic uranyl oxysalts) and Coll. S. Puccio.

[Roger Warin]

Saleeite

[Roger Warin]

Hi,
Two minerals in one Crystal !
Wyartite is black-purple in color. But it deteriorates superficially by decarboxylation into yellow epi-ianthinite (variety of schoepite).
Wyartite is the hydroxy carbonate of uranyl, copper and uranium.

[Roger Warin]

Hi,
Gold on uraninite is well known in Shinkolobwe.

[Roger Warin]

Hi
Here are extremely rare minerals.
The first is kolbeckite, scandium phosphate.
Scandium and yttrium are considered rare-earth elements because they tend to occur often in the same ore deposits as the lanthanides and exhibit similar chemical properties

[Roger Warin]

Hi,
Sharpite is a rare hydroxycarbonate of uranyl and copper with radially fibrous crust.
Black dots are heteogenite.