The metal does not react with moist air or dry oxygen but is oxidized superficially by moist ozone. It is quickly tarnished at room temperature by sulfur or hydrogen sulfide. In the molten state, silver can dissolve up to 22 times its volume of oxygen; on solidification, most of the oxygen is expelled, a phenomenon known as the spitting of silver.

How does it work? Silver can kill microorganisms by binding to their cells, without necessarily damaging human cells. Researchers are still looking into the mechanisms behind silver’s antimicrobial properties. However, there is no evidence that colloidal silver has beneficial antimicrobial effects when ingested by mouth.

Silver is antimicrobial. When it’s wet, the metal releases tiny particles called ions. These ions kill bacteria. Scientists think they damage bacterial cell walls, then get inside the bacteria to finish the job.