...an Antiseptic

The use of silver in medical and purifying applications is a growing industrial use that adds intrinsic value to the metal.

According to the Silver Institute:

While silver's importance as a bactericide has been documented only since the late 1800s, its use in purification has been known throughout the ages. Early records indicate that the Phoenicians, for example, used silver vessels to keep water, wine and vinegar pure during their long voyages. In America, pioneers moving west put silver and copper coins in their water barrels to keep it clean.

In fact, "born with a silver spoon in his mouth" is also a reference to health as well as wealth. In the early 18th century, babies who were fed with silver spoons were healthier than those fed with spoons made from other metals, and silver pacifiers found wide use in America because of their beneficial health effects.

Today silver is used in many health-care products. Specifically silver sulfadiazine is used by every hospital in North America to prevent bacterial infections in burn victims and allow the body to restore naturally the burnt tissue. It is used worldwide under the trade name "Silvadiene." Increasingly, wound dressings and other wound care products incorporate a layer of fabric containing silver for prevention of secondary infections. Surgical gowns and draperies also include silver to prevent microbial transmission. Other medical products containing silver are catheters and stethoscope diaphragms.

In a world that is showing increasing concern about the spread of diseases silver is being increasingly tapped for its biocidal properties. Research is ongoing on the use of silver and its compounds for therapeutic uses and on its potential use as a disinfectant in hospitals and other medical facilities. Already, climate control system components and ductwork using a silver containing coating are in place to prevent the transmission of bacteria that cause Legionnaires disease. The successful preparation of nano-sized silver particles offers additional capabilities in the fight against pathogenic organisms and research programs are under way to exploit these features.

And particularly as a water purifier:

Silver is employed as a bactericide and algaecide in an ever increasing number of water purification systems in hospitals, remote communities and, more recently, domestic households.

Silver ions have been used to purify drinking water and swimming pool water for generations. New research into silver compounds is providing physicians with powerful, clinically effective treatments against which bacteria cannot develop resistance.

An increasing trend is the millions of on-the-counter and under-the-counter water purifiers that are sold each year in the United States to rid drinking water of bacteria, chlorine, trihalomethanes, lead, particulates, and odor. Here silver is used to prevent the buildup of bacteria and algae in the filters. Of the billions of dollars spent yearly in the U.S. for drinking water purification systems, over half make advantageous use of the bactericidal properties of silver. New research has shown that the catalytic action of silver, in concert with oxygen, provides a powerful sanitizer, virtually eliminating the need for the use of corrosive chlorine.