wrong formula for Owyheeite

the current formula for Owyheeite is incorrect; it should be Ag3Pb10Sb11S28 (see lats Moelo's report)

Ag3+xPb10-2xSb11+xS18 (-0.13 < x > +0.20) from structural paer of Laufek F., Pazout R., Makovicky E. (2007) Eur. J.Mineral., 19, 557-566.

Marco, do you have a copy of that paper that you could send me. please?

Thanks for the kind endorsement on the Italian Type Minerals Book. The book is so interesting I didn't notice the photo on the front cover. Tubes of a Silver, Iron bearing Lead Antimony sulfide. Without knowing the % of each, it sounds like a Silver bearing Jamesonite. I have never heard of that. However at Van Silver we found Boulangerite tubes that were identified by Don Howard with his electron probe.



I busted my head trying to figure out some optical reason; diffraction, refraction, interference, camera effect, etc. for the red centres in these tubes. Sadly to no avail. Now your front cover suggests a silver mineral that makes tubes. It's easy to miss the tiny amount of Iron in Jamesonite and not much silver is required for a sulfosalt to transmit red light. That could be the answer to the red inside the tube!!! So I wonder if our "Boulangerite" is your new unknown mineral. We still have examples of these tubes from Van Silver. Would the people working on this new mineral be interested in examples for analysis???.



Edited 1 time(s). Last edit at 09/28/2009 01:59AM by Rob Woodside.

Ag, Fe, Pb and Sb are the more important element in the tubes (as you can noted from the unnamed codes), but most probably Cl is important, too.
Studies of the phase are current (Yves Moelo).
I will send the paper. Ciao.
Marco

Updated.

Uwe,
there is still a typo; this is not S18 but S28; sorry for bothering but let's try to get it right.
jean-Francois

Fixed. Thanks for the paper Marco.

Thanks Jean-Francois & Rob!

Hi Rob,
Could your mineral from Van Silver be tubulite?
It would be fun to find a third locality, just after approval of the mineral.
Best regards,
Georges.

Franckeite was found as a tubular (yes, tubular, not "tabular") inclusion inside a clear fluorite at the Hoei tin mine, Japan. I wonder how many other sulphosalts might be found in tubular habit? And the fact that a species can occur in both flat and tubular shapes raises the possibility that one day non-tubular tubulite could be found! Time to buy shares in the companies that make microprobes I suppose...

Very interesting!!! Thank you very much!!!

Can anyone send me the Tubulite paper ( Mineralogical Magazine, 76, 807-817)?

I wonder if Tubulite shows the same "red-eye" as the Van Silver tubes? I'll bet it could be eliminated with the photo aps that remove red-eye from people photos. The tubulites in our Gallery don't show "red-eye".

The SEM image of the Van Silver tubes in the 2000 article was taken by Don Howard and he identified Boulangerite. Presumably Parasterryite was the tube on the cover of the Italian Type Mineral book. I sent Prof. Moello one of the Van Silver tubes associated with Fizelyite and he replied that it was Owyheeite!!! Currently I'm lost somewhere between home renos and Afghanistan, and have been meaning to check my few owyheeites for transmission of red light. Has anyone noted this in Owyheeite? Usually Owyheeites are tiny flat lying xls that are hard to back light. Amusingly the Van Silver tetrahedrites show red lights, similar to Binnite, and that's the only red transmitting tetrahedrite I've ever seen, apart from the tennantite variety Binnite. So red transmission is probably not diagnostic, depending on thickness, impurities, and light intensity.

Curiouser and curiouser!!!

I have been fussing with this awful group of minerals using the electron probe since 1984.

They show such intricate exsolution and intricate intergrowths that I doubt there are many truly good analysis since the x-ray lateral resolution of the beam will almost always suffer from beam overlap on at least two phases, and produce a hybrid analysis.

Probably the same with XRD.

There is no practical "nano" in conventional mineralogical analysis.

The intergrowths of these minerals are more complex than a Jackson Pollock painting, but at least with a proper color chart you can determine what was on his palette.

Bart

I partially retract my immediately previous statement.

A scanning transmission electron microscope (STEM) and under some conditions, a high resolution transmission electron microscope (TEM) equipped with an x-ray spectrometer can image at the atomic level and provide x-ray spectra of the following layers in the lillianite species..

The acanthite layer, the bismuthinite layer, and the galena layers can be confirmed.

The analyses, however, are not easy to obtain by the common probe man. So not really practical.

I pretty much just like quartz, and galena. Too much solid solution in calcite and it's hard to discern marcasite from pyrite, wurtzite from sphalerite, and calcite from aragonite with the electron probe.

So if you want me to identify quartz or galena, I'm your probe lab. Oh. Darn. I don't think I can distinguish opal from quartz unless I I use my visual light optics in the probe to observe cathodoluminescense colors. I'm not sure if opal shows cathodoluminescence. I'll check.

Bart

Both Richard Gunter and Frank Kreutch have told me that low Fe and high Zn in tetrahedrite and tennantite permit the red transmission. Both Binnite and Van Silver Tetrahedrite have that chemistry.

Elsewhere Frank de Witt reports:
"In the Lengenbach quarry it was traces of Tl which caused the red internal reflections of non-Tl sulfosalts. Just after moving the old quarry upwards (from Lengenbach-I to Lengenbach-II) there was an increase in As-richer and Tl-rich minerals. At that time I was very active there and suddenly all "normal" sulfosalts seemed to have red internal reflections. This was not funny, it caused a lot of mental problems for the normal human beings without SEM-EDS "

Rather than living on Mindat, I must look at my Owyheeite to see if they have red transmissions. Anyone else found any?

Red lights in Tubulite?

Tubes seem to form either from curled plates ( Cylindrite, Potosiite, Graphite?, Molybdenite?) or by stacked rings like the Van Silver material. In tubulite are they stacked or curled?

I just checked my Tubulite (from the Italian locality) under high magnification, and it most certainly consists of stacked rings, like the Canadian material. Also, it shows apparent and relatively strong deep red transmission under strong light.

Lefteris.

And some beautiful related pictures uploaded yesterday: [www.mindat.org] [www.mindat.org]

Maybe these deserve a new analysis, in view of the recent description of Tubulite?

edit: should read "recent approval"

Lefteris.



Edited 1 time(s). Last edit at 12/03/2012 02:44PM by Lefteris Rantos.

Lefteris Rantos Wrote:
-------------------------------------------------------
>
> Maybe these deserve a new analysis, in view of the
> recent description of Tubulite?
>
> Lefteris.

Perhaps... the two phases are correlated but not so similar.
Description-type of tubulite is in progress.



Edited 1 time(s). Last edit at 12/03/2012 12:57PM by Marco E. Ciriotti.