Hi, Has anyone bought from this vendor: http://cgi.ebay.com/Ferric-Ammonium-Oxalate-1-Pound-/7616123966?pt=LH_DefaultDomain_0&hash=item1c5f4d43e#ht_500wt_949 <http://cgi.ebay.com/Ferric-Ammonium-Oxalate-1-Pound-/7616123966?pt=LH_DefaultDomain_0&hash=item1c5f4d43e#ht_500wt_949> thanks, Jacques