Throughout history silver has played a major role in all aspects of society. It has been used as a metal of choice for currencies, barter and trade. The bourgeois used it as a metering wealth status. Advances in medicine, electronics and others, are made largely to unique properties of silver. Silver, along side with gold, are the two precious metals sought after. The supplies are dwindling, while the demand is reaching an all time high.
Not surprisingly, the price of silver has more than tripled in recent years. Both silver and gold are the commodity to hedge against the falling dollar. It is becoming a "must-have" in personal investment portfolios.
Scrap silver is all around us. It comes from variety of sources with diversified metal purity. This article is designed to refine your own silver using readily available household chemicals. The methods you are about to be introduced to will produce more than 99% of pure silver!
The first step in refining is to dissolve the silver. The best way is to use dilute Nitric Acid. Good concentration is around 40 - 50%. Concentrated Nitric Acid is one chemical that will be hard to obtain.
Since 9/11 the availability of Nitric Acid has been drastically reduced and for a good reason. Nitric Acid is one of the main components to make explosives.
For our refining purpose we will need relatively small amount of Nitric Acid. To make this, we will use concentrated Sulfuric Acid. Sulfuric Acid is commonly used as a liquid drain opener, readily available from any hardware store. The one that we will use is more than 95 percent pure. The second ingredient needed is Sodium Nitrate. It is readily available fertilizer from any gardening store.
Pour 200ml of hot distilled water to a pre-heated 1liter Pyrex container, 1 quart mason jar will work. Add approx. 400 gm of Sodium Nitrate to dissolve (Potassium Nitrate can be used as well). Once the Nitrate is completely dissolved allow it to cool down well below the boiling point, but still hot.
To this solution SLOWLY add 110 ml conc. Sulfuric Acid while stirring. Do not allow the solution to boil. Cool the solution to room temperature.
Place the jar in the freezer and allow the solution to reach ~ -5 degrees Celsius. Once all of the precipitate has settled, pour off the solution to a glass container with a tightly sealed lid. Discard the precipitate. (Make sure not to transfer any of the sulfate salt) You have just made over 300ml of ~ 50% Nitric Acid.
Fair Word Of Caution! You are dealing with concentrated acids. Take all safety precautions when dealing with concentrated acids. Make sure you wear rubber gloves, face shield and protective clothing. If you spill any of the acid, wash with plenty of water.
To refine Silver, dissolve several ounces of scrap metal in Nitric Acid. This will take some time, but make sure that all of the metal is in solution. Heating the solution will speed up the reaction. Do Not Boil.
Filter the solution using several coffee filters, keeping the clear solution. The Silver dissolved is in the form of Silver Nitrate.
The easiest way to get the Silver to drop out of the solution is to use Copper. Copper pipe, plate or any piece of solid copper will do.
Suspend the Copper, using household twine in the acid solution. A white-grayish precipitate will start to accumulate around the copper.
Tap gently the suspended Copper, and the Silver precipitate will sink to the bottom. What you are doing here is replacing the Silver Nitrate with Copper Nitrate, causing Silver to drop out of the solution.
Allow the solution to sit overnight and all of the precipitate will settle to the bottom.
The remaining solution should be crystal-blue in color. If not, use more Copper to get all of the Silver out. Filter the solution using several coffee filters, this time keeping the precipitate. Wash it several times using distilled water.
There should not be any blue Copper Nitrate around the filter. Discard the spent solution and dry the filtrate. This precipitate is Silver.
Place the dry precipitate in a crucible or a small graphite container. In a circular motion, using a torch, melt the precipitate in nuggets or the desired shape.
The result is over 99% pure Silver!
