Hi there,
I too did some oxygen in opal (opasl-A and opal-CT) many years ago, and yes all
the precautions (mainly water) which Ronald Matheney and Labeyrie recommend
should be followed. The man who does now the largest amount of opal analyses is
Aldo Shemesh. He too is analyzing primarily diatoms. but an opal is an opal. His
e-mail is
[log in to unmask]
try to get in touch with him
yehoshua

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Yehoshua Kolodny,
Dept of Geology, The Hebrew University . Jerusalem. ISRAEL 91904
PHONES: off:(972) 2-6584685; dept.:2-6584686; home 2-636879;FAX:(972-2) 662581
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