Quest about Herderite

Hello,
a week ago i upload two photos of my Herderite, but there aren't on your database or in Herderite photo list, where there are only old images.
Why? i have to change the procedure? Don't like photo light or quality? what i have wrong?
Paolo

One of the managers did send you an email with some comments about the photos in question. (the specimen is unlikely to be herderite) (you also need to reclassify the photos as they are not thin section photos - thin sections are slices of rock 30 microns thick).

in my opinion they look similar to austrian finds at luftenberg, upper austria. pakistani or brazilian material is different. from what place are yours? the main question for me is if yours are indeed the extremly rare herderite or the very much more common hydroxylherderite (of course still rare, too!). by the way i uploaded a confirmed herderite in luftenberg gallery, the managers changed it to hydroxylherderite without a question....

Hello!

For me, they look like Herderite/Hydroxylherderite. You can not differ this two minerals by visual way! I have some xtals from the Steininger quarry near Luftenberg, Upper Austria. The exactly ID Herderite/Hydroxylherderite was made by infrared spectroscopy in Moscow!

Martin


"Komme gleich" ("I'll be right there") - Gotot

Hello,
i buy this specimen from Athos Locatelli at Edolo mineral show this mounth.
On the label there is written:
Herderite on Muscovite
Shigar valley, Skardu, Baltistan, Northern areas, Pakistan
The crystal is 2,6 x 2,0 x 0,9 cm
Paolo

Paolo:

You have changed the name of the specimens, on your photos, from "herderite" to "herderite-hydroxylherderite series", according to my suggestion, and I have already approved both.

Herderite is quite rare; to my knowledge there are only 2 confirmed localities of true herderite (that should contain more than 5,86% F, that is the mid-term between herderite and hydroxylherderite): Mogok, Mianmar, and Funil mine, Medina, Minas Gerais, Brazil; all other specimens on Mindat herderite photo gallery, from other localities, are questionable.

Hello all!

Luftenberg, Upper Austria, Austria is a further locality for Herderite (F>OH). This mineral was analysed by IR-spectroscopy (Brandstetter G. & Reich M. (1998); Brandstetter G. & Reich M. (1999)). So I don´t know, why Herderite is questionable for this locality here on Mindat.

See:

[www.mindat.org]
[www.mindat.org]

Martin


"Komme gleich" ("I'll be right there") - Gotot

thank you, martin!!!!
i uploaded the photo as herderite, not as hydroxylherderite. and it is indeed analyzed! is it possible for a mindat manager to add "herderite" to luftenberg locality? would be nice!
but keep in mind: most analyzed crystals from this locality are hydroxyl-herderites.......
by the way - i still think your crystal is europes best, but it needs a better photo!
[www.mindat.org]

I read the online article and as there were no data presented, the identification of herderite from Luftenberg is unproven. There is a statement that infrared analyses showed F>OH, but in the absence of a genuine statement of numerical data, standards used, etc. as is always present in an analytical report, the report cannot be regarded as valid. If there were a published discussion of the analyses, it may be possible to form a better agreement with the claim. The current information is insufficient to validate true herderite from Luftenberg. Meixner's report is not available, but as no data were cited, it is more than likely that, typical of old pre-Dunn reports, the mineral was simply called herderite as a series name. Are the original data still available? Who was the analyst and where was the analysis made? Does the laboratory have a good reputation for quantitatively determining fluorine contents? I'm sure it does, but there are many unanswered questions that need to be directly addressed. In contrast, the quantitative analysis of almandine is convincing. I don't mean to sound harsh, but herderite is a peculiarly evasive species with a long history of mis-identification.

Best Wishes, Van King



Edited 2 time(s). Last edit at 08/16/2012 03:06PM by Van King.