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[Jan Erik]

Sometimes I see Vanadinite xls on either gothite or hollandite. I have always belived that Vanadinite specimens with such a matrix comes from Taouz.

On the web it is often possible to see such specimens labeled Mibladen.

Could anybody out there give me the correct source?

[Jordi Fabre]

Jan,

As far as I know all the Vanadinites on black Hollandite (no Goethite, I analyzed them) matrix came from Taouz. Its shape and color is also pretty characteristic: frequently the crystals are doubly terminated and prismatic and them shows a color a little bit more orange than the ones from Mibladen, although some Vanadinites from Taouz could also be pretty reddish.
However the black Hollandite matrix is very characteristic, no finds in Mibladen with this kind of matrix.

Jordi

[fmmtaouz]

Hi Jordi , you are totally right , no finds of that kind of vanadinite on that type of matrix from Mibladen , despite some label them Mibladen , i bet maybe because they purchase them without knowing the exact locality so they put Mibladen as its mostly famous of Vanadinite , your message however confused me , i have Mineral of that kind from a Mine in Taouz , and i so far think the orange Vanadinite is on botroydal Goethite matrix , while you said it s Hollandite , i would like to explain me what difference bertween Hollandite and Goethite , here is a picture of a recent find . thanks

[Jordi Fabre]

No big difference between Hollandite and Goethite, at least considering its visual appearance. The difference is by its chemical composition, Goethtite is an iron mineral: a-FeOOH and Hollandite is a Barium and Manganese oxide: Ba(Mn4+,Mn2+)8O16.
I analyzed several specimens from Taouz and I always got Hollandite as result. I don't analyzed the matrix of this kind of Vanadinite, so it could be Goethite, why not, but in my opinion if it comes from Taouz and from the same mine/shaft where the classic Vanadinites comes, it could be Hollandite too.

Jordi

[fmmtaouz]

maybe that is true , because we find in same Mine manganese Oxide minerals (Pyrolusite)...

[Jan Erik]

I will thank you both Jordi and fmmtaouz for the statement. It will clear up a lot for me. Otherwise mislabeling is in my opinion a huge problem not only from Morocco but from many countries.

Since a do collect minerals from Morocco, and fmmtaouz is right in the middle of the source, could you leave an e-mail address to get in contact?

[Carles Curto]

As Jordi well says, Vanadinite on Hollandite matrix is characteristic from Taouz and it is not known from Mibladen. Information on labels of minerals for sale is not always correct, too much frequently is doubtful.
Fortunately, on our days there is a lot of good and precise data on webs, books and magazines to correct mistakes.
The most actual description of the locality (according to the new administrative division of Morocco, 2002) is: Taouz (mine), Taouz, Tadaout, Errachidia (province), Meknes-Tafilalt (wilaya), Morocco.

I join you a concise bibliography that can help you on Moroccan Vanadinite.

Gaudefroy, C. 1952. Etude cristallographique de la vanadinite du Tadaout, prés de Taouz, Maroc Sud-oriental. Not. Serv. Géol. Maroc. 6(95): 237-246. 2 pl.

Jahn, S., Bode, R., Lyckberg, P., Medenbach, O., Lierl, H-J. 2003. Marokko. Land der schönen Mineralien und Fossilien. Bode Verlag. 535 p. Haltern.

Jouravsky, G. 1959. Psilomélan plombifère de Tadaout, prés de Taouz. (a Description provisoire des espéces minérales du Maroc 9). Not. Serv. Géol. Maroc. 4. Notes et Mem. 17(144): 148-150.

[Jan Erik]

I really thank you Carles for the further information you came up with, according to the Taouz occurence.

For me it is very importened that the occurence and labeling specimens follows each other correctly.

[Mike Hopkins]

We recentley purchased one of these from an old collection and the label says limonite. We believe it to be Hollandite or Goethite. What do you think? It is a very aesthetic specimen. How long ago were these mined?

[Jordi Fabre]

Mike,

No doubts about the black mineral: Hollandite, nor about the locality: Taouz, but I ignore when it was mined.
It could be (more or less) 5 years old (one find) 10 years old (an other find) or even earlier (people found this kind of Vanadinite on Hollandite several times on the past).

Hopefully it helps

Jordi

[Carles Curto]

Those vanadinites, well known since 1950, were essentially mined (for collection) in Taouz since the beginnings of the eighties (especially between 1982 and 1985) to 1990. Some of them (as the pictured one) had tabular habitus, but some other were short prismatic, doubly terminated and had two different terminations, flat (pedion) and pyramidal. Since 1990 they had been progressively scarce and actually they can be considered as rare.

[Mike Hopkins]

Thanks Jordi

Mike

[Mike Hopkins]

Carlos
You are a wealth of knowledge.
Thank you very much
I love this forum

Mike