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Silver profits in water

The antibacterial properties of silver were known 2,000 years ago. Back in the days of the Roman Empire, people knew enough to throw silver coins into water cisterns as a low tech way to kill germs – despite not yet understanding the scientific mechanism of why this made water safer to drink.

A silver Roman pitcher. Image courtesy of Bibliothèque nationale de France, Département des monnaies, médailles et antiques, Paris

A silver Roman pitcher, circa 1-100 A.D.Image courtesy of Bibliothèque nationale de France, Département des monnaies, médailles et antiques, Paris

There have been portable and household water filters on the market for decades that use silver ions to kill bacteria. Research has determined that silver destroys bacteria by a physical process. What that means is that bacteria cannot mutate to become immune to destruction by silver. Such mutations render most antibiotics relatively ineffective over time.

At an American Legion convention in Philadelphia in July 1976, more than 200 people became sick and 34 died from a germ in the water supply now labeled Legionella bacteria. Because of this outbreak, the malady is called Legionnaire’s Disease. This germ does not harm normally healthy people but causes respiratory distress among people with compromised immune systems. The disease can be contracted by drinking the infected water if it accidentally goes down the windpipe or by breathing in small water droplets suspended in the air.

At first, the standard means of trying to eliminate these virulent bacteria from an infected building’s water supply was to flush out the entire system with very hot water.

Unfortunately this did not completely destroy the bacteria. In any water system, there are dead ends and other obstacles that just don’t get thoroughly flushed. Although the bacteria count initially fell sharply, the counts again rose as time passed.

However, it was discovered years later that simply adding a minute quantity of silver ions to such infected water systems 100 percent eliminated this bacteria – within 24 hours.

Recently, the Wake Forest Baptist Health – Lexington (N.C.) Medical Center announced it will be installing a silver-copper ionization water purification system. The hospital’s administration had detected evidence that the facility’s water supply was infected with Legionella bacteria. No injuries or illnesses there had yet been attributed to these bacteria, but the silver-copper ionization equipment was being installed as a precaution.

It takes only minute quantities of silver to kill bacteria. Because silver is so effective at killing bacteria, it could be cost effective in water systems of almost any size, and is also highly safe for human consumption in many formulations and dosages. It would not surprise me to see silver being added to some municipal water systems within the next decade. Once the efficacy and efficiency of killing germs is proven, I foresee most modern municipal water systems will be treated with silver ions within the next 20 years.

Even though only small quantities of silver would be needed to treat water supplies, the total used for water purification nationwide would add up to millions to tens of millions of ounces of new demand annually (or more). All of which provides even more optimism for even higher silver prices in the long-term future.

Patrick A. Heller was the American Numismatic Association 2012 Harry Forman Numismatic Dealer of the Year Award winner. He is the owner emeritus and communications officer of Liberty Coin Service in Lansing, Mich., and writes “Liberty’s Outlook,” a monthly newsletter on rare coins and precious metals subjects. Past newsletter issues can be viewed at Other commentaries are available at Coin Week ( His radio commentaries titled “Things You ‘Know’ That Just Aren’t So, And Important News You Need To Know” can be heard at 8:45 a.m. Wednesday and Friday mornings on 1320-AM WILS in Lansing (which streams live and becomes part of the audio and text archives posted at

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