Dear all, Stan Halas informed me that he supplied the original material (sphalerites) for the production of the IAEA-S-1, IAEA-S-3 and IAEA-SO-6. The story is that Brian Robinson did produce the final reference material (AgS: S-1 to S-3) from the sphalerite material provided by Stan Halas it was rather an incomplete than incorrect story I gave before. I wanted to correct this to give honour to whom deserves it. Best wishes, Pier. **************************************************************** Delta Isotopes Consultancy Dr. Pier A. de Groot Pastoor Moorkensstraat 16 2400 Mol - Achterbos Belgium Tel. +32 (0)14 326 205 e-mail: [log in to unmask] or [log in to unmask] Visit my WEB-site about my ³Handbook of Stable Isotope Analytical Techniques², with a link to the Elsevier web site on the handbook (place your order there): http://users.pandora.be/handbook/index.html last update: August 15, 2005 Volume I is now available. Volume II is expected to be available second half of 2005. ****************************************************************