>Dear all,
>
>Does anyone know (have) a standard of sulfate for the oxygen isotopic
>composition?
>

Like other colleagues that have responded, the only sulphate-O reference
material I know of is NBS-127.

However, from my point of view, additional reference materials with delta
18-O different enough from +9.3 permil are badly needed.

Some months ago I asked the group if anybody had an alternative/complement
to NBS-127, and I am asking the same question again:

Is anybody willing to get involved in the search for other complementary
materials to be used as reference for sulphate-O? Reagent-grade BaSO4
should be an easy target, abundant enough and homogeneous enough (at least
within individual batches) to test.

If anybody is interested or has additional comments, I'm willing to go
ahead, but I need some other Labs to get results worth trusting.

Cheers,

Clemente


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Dr. Clemente Recio
Stable Isotope Laboratory
Fac. de Ciencias
Univ. de Salamanca
E 37008 - Salamanca
      Spain

Phone: (+34) 23 29 44 00 Ext. 1540
Fax:   (+34) 23 29 45 14
E-mail: [log in to unmask]
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