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Do-It-Yourself Silver Refining

Refining silver is fundamentally a three-step process. First, you obtain silver containing ores or materials. Then you add nitric acid, which reacts with the silver to form a liquid silver nitrate compound, which can be poured away from the remaining impurities. Finally, you add silver precipitate crystals, around which pure silver solidifies into crystals, separating from the nitrates. It sounds simple, but it involves the use of dangerous chemicals and requires that you wear protective gear, and work in a very well-ventilated area. A key issue is that it is difficult to obtain concentrated nitric acid since the events of 9-11. A dilute solution of at least 40 percent will work fine, but the reaction will be slower.

Things You'll Need

Rubber gloves
Rubber apron
Safety goggles
Two five-gallon buckets
Nitric acid
Hard plastic or glass stirring rod
Screen filter
Silver precipitant crystals
Water
Measuring containers
Soda ash
Aqua ammonia

Instructions

- 1
  Put on all safety equipment before you begin. Weigh all the silver you will refine. You will need 150 ml of nitric acid for every ounce of silver.
- 2
  Place the silver into one of the buckets. Do not fill the bucket more than one-third full of silver. If you have more than this, get more buckets. Pour in the proper amount of nitric acid based on the weight of the silver you are refining. The silver will immediately react to the acid, foaming and bubbling as it dissolves. You may stir the bucket occasionally to speed the process. Wait until the solution has stopped fizzing before going on to the next step.
- 3
  Put the screen filter atop the second bucket and pour the mixture through the filter. This keeps out impurities while allowing only the liquid silver solution into the second bucket. Remove the filter and place it back into the first bucket.
- 4
  Add one ounce of silver precipitant crystals for every 40 ounces of liquid. as you pour the crystals into the solution, pure silver lumps will form around them and drop to the bottom of the bucket. Silver precipitant crystals are sometimes called hydroquinone and are used in developing black and white film. You can get them at larger photo supply stores.
- 5
  Let the solution sit for at least 30 minutes after you have added the silver precipitant crystals to allow it to draw out all the silver. Then pour the remaining solution back through the filter into the first bucket. The filter will capture the silver clumps. Put those clumps back into the empty bucket.
- 6
  Put soda ash into the bucket with the nitrate solution in order to neutralize the remaining acid.
- 7
  Rinse the pure silver thoroughly with water. Place a drop of aqua ammonia on the surface of the silver. If it turns a bluish color, you still have some liquid impurities on the silver. Rinse and repeat this test until no blue color shows up. Then rinse it once more and set it out to dry.

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