Hi Ibrahim, try to contact Mr. Brauns at the Curt-Engelhorn-Zentrum of Archaeometry in Mannheim, Germany. (http://www.cez-archaeometrie.de/ )

Hi Judit, great thanks for your answer. I will immediately contact him. Cheers...

Dave Selby at DURHAM - https://www.dur.ac.uk/dgc/research/total_laboratory/

Holly Stein USGS - http://earthdynamics.org/holly/Holly_Stein.pdf

Arizona Geochron Centre - http://www.geo.arizona.edu/agc/about.html

Dear Adrian and Mehdi,

Thanks so much your your help. I will be in contact with them as well.

All the best,

Ibrahim

Thank you Sisir. Hope everything goes well over there. All the best from Turkey,

Ibrahim

Dear Abrahim,

Just to be clear, David Selby and his group  do not carry out in-situ, by which I take it you mean laser ablation MC-ICP-MS or SF-ICP-MS, Os isotope analyses of sulfides.

Myself and Chris Dale on the other hand do carry out in-situ Os isotope analyses by laser ablation MC-ICP-MS but on platinum group metal alloy grains rather than sulfides. We are the only people at Durham carrying out such in-situ Os isotope analyses.

The problem with the in-situ Os isotope analysis of sulfdes is that generally the sulphides are so small and the Os concentrations too low to yield an Os beam size that provides meaningful/accurate Os isotope data. In some cases the Os signal is so low that to perform a mass bias correction during the measurement it also proves necessary to aspirate an Ir solution and mix that with the laser ablation product. Performing accurate Re corrections on the 187Os is also very difficult at low Os beam intensities. There is also the issue that if you've polished a section to expose a sulfide then you will have lost some of that sulfide and if there has been any exsolution it may have fractionated the Re/Os ratio such that the Re/Os ratio you measure on the remaining sulfide may have no bearing on the measured Os isotope composition. In other words the Os isotope compositions is unsupported by the measured Re/Os ratio. A couple of references to look at that discuss some of the issues with in-situ Os measurements are :

Pearson N.J., Alard O., Griffin W.L., Jackson S.E., O'Reilly S.Y., 2002. In situ measurement of Re-Os isotopes in mantle sulfides by laser ablation multicollector–inductively coupled plasma mass spectrometry: Analytical methods and preliminary results. Geochim. Cosmochim. Acta., 66, Number 1037-1050(14).

G.M. Nowell, A. Luguet, D.G. Pearson & M.A. Horstwood (2008a). Precise and accurate 186Os/188Os and 187Os/188Os measurements by Multi- Collector Plasma Ionisation Mass Spectrometry (MC-ICP-MS) part I: solution analyses. Chemical Geology 248: 363-393.

Norm Pearson and Bill Griffin at GEMOC are probably the main group carrying out this kind of analysis so I would contact them if this is really the way you want to go.

Hope this helps. All the best

Geoff

Dear Geoff,

Thanks so much for all these explanation and help. These will help me a lot.

Ibrahim