Some types of "silent" light switches, may contain liquid mercury in a metal or glass enclosure.
It is illegal to place mercury-containing products in the trash.
If mercury is spilled in your home, do not vacuum it up. Immediately call the Minnesota Pollution Control Agency at 651-649-5451 for proper cleanup procedures, or visit the U.S. Environmental Protection Agency (EPA).
Keep the mercury switch intact and bring it to a household hazardous waste collection site for free.