FMF - Friends of Minerals Forum, discussion and message board

[BHmineral]

Hi,

I'm in doubt about the question: are Sphaerocobaltite and cobaltocalcite the same mineral or are there differences between these minerals?

Thank you

[GneissWare]

[Jordi Fabre]

"Cobaltocalcite" is a not existing species, is just a name used for a cobaltoan variety of Calcite. Please check it in the official IMA/RUFF list: https://rruff.info/ima/ or in Mindat: https://www.mindat.org/min-1094.html

[BHmineral]

Ok.

Thank you very much.

Eduardo

[Peter Megaw]

A related subject is the common mislabeling of calcite that is pink because of manganese as either sphaerocobaltite or cobaltian/cobaltoan calcite (or even cobalt-rich calcite).

This mislabeling is widely true of the manganese bearing calcites from the Aranzazu Mine at Concepcion del Oro, Zacatecas, Mexico. These have been analyzed and they contain NO cobalt at all, while being high in manganese. This is beautifully displayed under SWUV...they fluoresce bright red-orange

[Roger Warin]

Cobaltoan calcite contains not more than 1% of cobalt. As said Jordi, it is only calcite, not another mineral species.
This small amount of cobalt does give a beautiful purple color to this single crystal whose ternary termination is an obtuse rhombohedron {01.2}.

[Roger Warin]

Spherocobaltite, Kakanda (Katanga).

Here is a specimen of spherocobaltite, CoCO3.
Kakanda is a group of three mines (North, East and South) and two hills, Disele and Fungurume.
Kakanda is located just west of Likasi in Central Copper Crescent.

In the Mindat.org page, this mineral exists as spherocobaltite.
In Fleisher’s Glossary, it’s discredited. Why? Is there no mineral whose composition is CoCO3? Wow, very odd…
The crystal habit is special. It looks like rosettes with petals are saddles shaped (as dolomite).
The purple color is very dark, difficult to shoot.