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Does real stainless steel get rainbow color/blue tinting ?December 18, 2008
I purchased supposedly 18/10 stainless steel cookware and on first use, the pot developed rainbow/blue discoloring. Is this normal and safe? Also, is it mandatory for companies to print the stainless steel content on the item...should my cookware be imprinted with 18/10 because it is not?
buyer/customer - Tomball, Texas, USA
January 7, 2009
Hi, Melanie. 18/10 is a good grade of stainless, so some manufacturers may mark it such with pride -- but stainless steel is not a precious metal and I doubt that there is any rule anywhere that says they must. Metals can discolor from excessive heat -- you've probably seen exhaust pipes on motorcycles that have stained blue or gold -- but I think the discoloration you are seeing is probably a very thin layer of burnt-on oil.
Ted Mooney, P.E. RET
Pine Beach, New Jersey