The tarnish of copper, brass, tin, and other metals often stains
textiles. To remove, apply vinegar, lemon juice, or a 10-percent
solution of acetic acid. Rinse well as soon as the stain has dissolved.
Do not use chlorine bleaches or sodium perborate to remove these stains.
Mercury or quicksilver removes lead or solder stains from rugs or
clothing. First scrape off as much of the lead as possible with a dull
knife. Then pour mercury on the stain and work with a stick until the
mercury absorbs the stains.