The 304 stainless steel is a FCC structure. The Chromium atom is in a substitutional position and a coordination number of 12 (closest neighbors). Because valance states of 3,4,6 are stable, chromium can occupy either the tetrahedral or octahedral positions in the oxide lattice. The oxide film on the stainless steel is a spinel structure (Fe,Cr)2O3. It most likely is a -4 in the stainless steel oxide. The term Hexavalent, for dissolved ions in solutions is different than in condensed matter (solids). Unified Numbering System (UNS G10100) Carbon steel 1010, C 0.08-0.13, Mn 0.3-0.60, P 0.040 max S 0.050 max. Note: that this is a general spec, your specific piece will need to be looked at for specific elemental list. Say if your 1010 came from a remelt shop then things like chromium and nickel will be found. If you are purchasing new steel be sure to ask for a CMTR (Certified Material Test Report). Also, you can ask for more elements but only elements on the spec will be included in the standard CMTR. Rob > From: "srimani Bhamidipati"> Date: 2005/05/09 Mon AM 06:17:40 EDT > To: MEMS-talk@memsnet.org > Subject: [mems-talk] CLC 1010 steel > > Can anyone of u please tell me whether Chromium present in AISI 304 > stainless steel is hexavalent.Also what is the composi0ion of CLC 1010 > steel.Can anyone suggest me a link where I can get info on CLC 1010 steel?