Unfortunately, “Stainless”, “INOX” or “Rostfrei” designated steel does not mean that the material will not discolour if improperly cleaned or stored. The marks that can result are for the most part aesthetic blemishes. If you wish to remove them, you may rub gently with a slightly damp microfibre cloth or a cotton ball soaked in white vinegar. Do not use abrasive cloths or cleaners, or anything containing chlorine.