Most of the silver, gold, brushed nickel or satin silver metal hardware and components of shower enclosures are anodized aluminum. Aluminum is lightweight and non-rusting and is anodized to give it color and to seal it against corrosion and pitting. Some glass cleaners can damage the anodizing which then leaves the aluminum at risk for pitting. Once the finish is damaged, it cannot be undone. White spots can result from using alkaline and phosphoric acids that are found in many cleaners. Read labels on all cleaning products before using them on your shower glass, frames and hardware. What might be good for cleaning glass, can be harmful to the framing and hardware.
The best practice is to wipe down the frame and hardware after each shower use, drying off the metal surface. This will reduce water spots from forming and in the long run, reduce the need for cleaning with products.
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