Despite its anti-rust properties, you may see some stainless steel that appears to have rust on the surface. This is known as tea staining. Tea staining is rust forming on the surface of stainless steel, causing a discolouration similar to a tea stain. It may not look appealing, tea staining is only cosmetic and does not affect the functionality or integrity of the stainless steel. Regular cleaning and maintenance with a mild soap and water solution can remedy the discolouration.