Hi TNuts, got this from Bev one hundred years ago. Just wonder what method would be best for examining possible nickel that has diffused through Immersion Gold and then oxidized, and if somebody even tried? We have tried TOF-SIMS, machinist doing good job, but interpreting not for poor grassroots. E.g. number 7) below, what in George W Bush's name is that? Ingemar Hernefjord Ericsson Microwave Systems --------------------------------------Year 1898, or maybe my marking meant something else----------------------------------- SEM/EDX will not tell you whether you have tin(II) or tin(IV) oxide. In fact, unless you have a very $ expensive EDX it won't tell you if there is any oxygen there at all! Most EDX don't go any lower than sodium in the periodic table. To determine the type of tin oxide present you have several options, all of them but one not easy: 1) top-of the-line geology grade mass spec with quantitative capability 2) Auger (will detect oxygen and I presume from the amount you might be able to infer type of oxide?) 3) ESCA (determines oxidation state of all elements) 4) Mossbauer Spectroscopy (determines oxidation state of tin and some other elements) 5) Raman Spectroscopy (like infra-red spectroscopy, measures molecular vibrations. There are definite differences between stretching vibrations of tin(II) and tin(IV). May not give good spectra if a lot of organic crude around that will cause the sample to fluoresce.) 6) And then there are really fancy things like EELS and PAS, which I know very less about! :) and finally 7) If there is an accessible, flat surface with this stuff on it you and just use SERA (Sequential Electrochemical Reduction Analysis), a form of chronopotentiometry, which will tell you which oxide and how thick. regards, Bev Christian Nortel --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------