I let the calcium-encrusted chrome plated hardware from my 1940-vintage
tub soak in a solution called "Calcium Lime & Rust Stain Remover". Most
of the calcium came off in a matter of 30 minutes or so, and there was
no other damage, so I decided to let it soak for a few hours to get
really clean.

Unfortunately, when I came back, the chrome was discolored to a light
copper tint.

The active ingredients in this solution are hydrochloric acid and
sulfamic acid. Does anyone know how to get the chrome back to its
original color?

Thanks