Features of the silvering process
Before and after silvering copper
- Copper or brass products are usually coated with silver; parts made of aluminum, steel and other metals and alloys can be processed quite well. When in contact with these substances, the silver compound can decompose, releasing metallic silver. This property of the substance is used to treat various surfaces.
- Brass objects lend themselves best to silvering, since silvering lighter metal requires less solution. Copper or steel with a dark surface can show through under a thin layer of silver, so to process them you need more than 10-15 microns of solution. Some metals are pre-coated with a layer of copper for better reaction.
- Silver plating work at home is carried out in a room that should be well ventilated. Before processing, the copper surface must be degreased using organic solvents or alkaline solutions to remove any impurities (oxides, fat, oil).
- During the work, you will need pieces of soft cloth or leather with which the paste is applied to the product, flannel for polishing the surface and rubber gloves.
Chemical silvering method
- For the silvering process, the chemical composition of the solution is adjusted: hyposulfite (1 l) is mixed with formaldehyde (6-10 drops) and ammonia (4-6 ml) is added. Carrying out the adjustment allows you to obtain a silver coating.
- Copper products are pre-treated. The part is cleaned until shiny, then it needs to be boiled in a soda solution and rinsed well in water. After preparation, the object is immersed for 1-1.5 hours in a container of photographic solution.
- At the end of the procedure, the surface is covered with a silver film, the quality of which is determined by the concentration of silver in the composition. The product is washed in water, dried and polished with a soft cloth to add shine.
- In order to silver plate copper, you can simply rub it with matte photographic paper in a hyposulfite solution.
- To do this, sheets of photo paper are cut into pieces and immersed in a solution diluted in accordance with the instructions on the package.
- The prepared product is dipped into a container and processed (rubbed) using an emulsion layer of paper. Gradually, a silver coating appears on the surface of the product. At the end of the procedure, it is washed and wiped with a soft cloth.
- Prepare a solution of hyposulfite (300 ml), 2 ml of ammonia, 2-3 drops of formaldehyde, which is then placed in a dark place. The cleaned product is immersed in liquid for 30-90 minutes, then dried and wiped with a rag.
Application of paste
Silvering Copper with Lapis Pencil
- The home method of silvering using lapis pencil (silver nitrate) is quite complicated, but gives a denser coating.
- To prepare the mixture, 2 g of silver nitrate is dissolved in 300 ml of water.
Hydrochloric acid or a 10 percent solution of table salt is gradually added to the composition until silver chloride flakes stop falling out. The resulting precipitate must be filtered and washed well.
- Next, sodium hyposulfite (20 g) is dissolved in 100 ml of water and silver chloride is added there. When the substance stops dissolving, the resulting mixture is filtered and mixed with ground chalk or tooth powder. As a result, it should look like liquid sour cream, which is used for silvering. Copper is rubbed with this mixture until a dense silver film is obtained.
- For the second method, you need to mix the following ingredients:
- silver chloride 6 g;
- table salt 8 g;
- potassium tartrate (tartar) 8 g.
The prepared powder is mixed well and ground in a mortar. The mixture is stored in a dark glass container. Immediately before use, it must be diluted in water to form a liquid paste, which is used to rub the previously cleaned part.
- The following substances are mixed and dissolved in water to form a liquid slurry:
- cream of tartar 4 g;
- ammonia 2 g;
- lapis pencil (silver nitrate) 1 g.
The finished mixture is applied to the fabric and rubbed onto the metal surface until shiny.
- Prepare and carefully filter the composition from the mixture:
- silver nitrate 10 g;
- potassium cyanide 25 g;
- water 100 g.
Lapis pencil (silver nitrate) is dissolved in 50 g of water, a solution of potassium cyanide and 50 g of distilled water are added to the resulting composition.
The resulting substance is mixed with a mixture of 10 g of cream of tartar and 100 g of washed chalk into a liquid slurry. Metal products are treated with the paste, after which they are rinsed with cold water and dried.
Using a powder composition at home has advantages over liquid solutions. The powder has a longer shelf life; in a dark room it retains its properties for more than a year. Liquid solutions have a shelf life of several days. 
Silver plating using heat
- Mix and dilute with water to obtain a creamy consistency:
- silver chloride 100 g;
- cream of tartar 600 g;
- table salt 600 g.
The finished composition is tightly sealed in a brown glass vessel and placed in a dark place.
To carry out silvering, a small amount of the resulting mixture is dissolved in water and brought to a boil, where the copper parts are processed for 15-20 minutes. The silvering process is carried out in a copper cauldron, into which objects are placed in a porcelain sieve. The solution is prepared at the rate of 3 tbsp. spoons of mixture per 5 liters of water.
The silver coating turns out matte and to add shine, a composition is prepared from the following ingredients:
- water 4.8 l;
- sodium sulfide salt 300 g;
- vinegar-lead salt 100 g.
When the solution is heated to 70-80 degrees, lead sulfide is released. The parts are lowered into the boiler for 10-15 minutes and upon completion the metal surface becomes shiny.
- Silver chloride, obtained from 25 g of silver nitrate, is mixed with cream of tartar (150 g), table salt and water to a liquid slurry. The finished mixture is kept in a dark container.
Silvering is done in a five-liter enamel cauldron, into which water is poured and brought to a boil. Add 2-3 tbsp to the container. spoons of a mixture that does not completely dissolve. Copper parts are treated in a boiling solution in a clay or porcelain sieve, while stirring them with a glass or wooden rod. To repeat the procedure, a new mixture is added to the boiler.
Silver plating by immersion in solution.
- To obtain a denser film of silver at home, prepare the following solution.
- ammonia 70 g;
- silver chloride 10 g;
- crystalline soda 40 g;
- potassium cyanide 40 g;
- table salt 15 g.
All these substances are mixed and distilled water is added to a volume of 1 liter. Metal parts are lowered into the container at the same time as a piece of zinc or mounted on a zinc plate.
- To prepare the solution, a composition is made from the mixture:
- silver nitrogen salt 11 g;
- potassium cyanide 60 g;
- exhausted chalk 750 g;
- water 60 g.
Take one part of the mixture and add two parts of distilled water, and immerse the metal part in the resulting paste. Large objects can be wiped with a sponge or rag soaked in the solution. Upon completion, the product is rubbed with chalk and polished with a piece of leather.
- Contact silvering method
- carbon-silver salt 10 g;
- sodium sulfide salt 100 g;
- water 100 g.
The substances are mixed and dissolved in water, stirring constantly during the process. The finished solution is drained, filtering off the precipitate. The products are lowered into a container with a solution, where they come into contact with a zinc stick.
Video: Silver plating in solution
Silvering copper and brass at home does not require special skills or rare reagents. There are many techniques for coating another metal with silver. This is done in order to give it not only decorative properties: silver-plated metal will have other technical specifications. The silvering process involves the ability of certain silver compounds to decompose in the presence of metals, releasing metallic silver.
Silver plating at home
Silver coating of metals has its own characteristics:
- The most commonly plated materials are brass, copper or zinc. Aluminum and some other metals lend themselves well to silvering.
- Brass lends itself best to silvering. Copper is much darker, which affects the color of the final product: due to the thin layer of silver plating, dark metal is visible. To avoid this, the products need to be coated with a thicker layer, and this is technologically more difficult.
- At home, this procedure should be performed in a well-ventilated area. The surface is first cleaned of grease, oil and dust using alkaline solutions.
There are several methods of silvering, some of them require special equipment, others are easy to do at home. The most common method is the chemical method of applying silver.
Chemical silver plating
The most simple technique consists of placing the prepared parts in a waste hyposulfite photographic solution. It is necessary to place the items on which silver is applied for 1.5 hours, then remove them and polish them. To obtain a shiny coating, the solution is adjusted. To do this, add 4–6 ml of ammonia and 4–6 drops of formalin per 1 liter of used fixative.
Another method for silvering metal is to rub the part with matte photo paper in a fresh fixative solution. To do this, you need to cut sheets of photo paper into pieces and place them in the solution. Then lower the prepared product and rub it with an emulsion layer of paper until a silver coating appears. Afterwards, wash and wipe the product with a cloth.
Silvering when heated
There are several ways to coat a copper product at high temperatures.
For the first method, prepare a solution of six parts salt, one part silver chloride, and six parts cream of tartar. Add a little water to it until it becomes a paste. This solution should be stored in glassware dark color.
Copper products are placed in 5 liters of water, to which 3 tbsp is added. l. this solution and boil for 20 minutes. The silvering itself is carried out in a copper cauldron, into which objects are placed on a porcelain sieve, stirring continuously. The products are immediately covered with a silver film.
However, the method will not give a shiny coating; for this, the product must be kept for 10–15 minutes at a temperature of 70–80 degrees in a solution of four liters of water, 300 g of sodium sulfide salt and 100 g of lead acetate salt.
Brooch before and after silver plating
Silver plating using paste:
- A more dense coating is obtained by using silver nitrate, or lapis pencil. To do this, take 2 g of silver nitrate and dissolve it in 300 ml of water. Gradually, hydrochloric acid and table salt diluted with water 1:10 are added to the composition; do this until silver chloride in the form of flakes stops falling out. After this, the precipitate is filtered and washed. Next, the resulting silver chloride is added to a solution with 20 g of sodium hyposulfite and 100 ml of water. After the silver has finished dissolving, the mixture is filtered and mixed with chalk. The resulting paste is used to rub copper to obtain a silver coating.
- There is another way. Take 6 g of silver chloride and add 8 g of table salt and cream of tartar. This powder must be stirred and crushed in a mortar. The paste is obtained by dissolving in water.
- For the next method, the following ingredients are dissolved in water to obtain a paste: 2 g of cream of tartar, 4 g of ammonia and 1 g of silver nitrate.
- Silvering of copper can also be carried out with such a paste. Dissolve 10 g of silver nitrate in 50 g of water, then add a mixture of water (50 g) and potassium cyanide (25 g) to the solution. To obtain a paste, add a mixture of 10 g of cream of tartar and 100 g of chalk. After treatment with the paste, metal products are rinsed and dried.
Galvanic silver plating
Another method of applying silver is through electroplating. The electrolyte in this case will consist of the following components:
- 10–15 g of silver chloride;
- 15–25 g of potassium iron-nitrogen;
- 15–25 g of soda ash;
- 1 liter of distilled water.
Each component is pre-dissolved in boiling water. Boil the components of the solution together for 1.5–2 hours. The temperature at which the galvanization process takes place is 18–20 degrees at a current density of 0.1 A/dm3. I use graphite plates as an anode.
The silvering process is simple and can be easily repeated. It is not only these metals that can be coated. In order to plate silver on a metal that cannot be silvered, you must first coat it with a thin layer of copper.
Some silver compounds decompose when they come into contact with zinc, iron, copper and other metals, releasing metallic silver. This property of silver salts can be used to coat any metal surface with a layer of silver.
The following recipes for silvering metals are suitable for zinc, copper and brass. If it is desirable to silver plate another metal, then it must first be coated with a thin layer of copper.
Recipe 1
- silver chloride 300 g;
- table salt 300 gr;
- exhausted chalk 200 g;
- potash 600 gr.
Step 1. Mix these substances.
Step 2. Clean the item completely from dirt and traces of fats or oils.
Step 3. Rub with a raw piece of the above mixture.
Step 4. Rinse with water and polish.
Recipe 2
- silver nitrogen salt 100 g;
- potassium cyanide 300 gr.
Step 1. Both compositions are mixed.
Step 2. Spread the resulting dough-like mass onto a woolen cloth. They rub the object with it.
Step 3. The object is washed with water and rubbed with a piece of leather until it shines. The result is an even, beautiful layer of silver.
When using this recipe, we strongly recommend wearing rubber gloves and generally working with extreme caution, since potassium cyanide is one of the strongest poisons and you need to be extremely careful when working with it.
Recipe 3
- silver chloride 300 g;
- table salt 600 gr;
- cream of tartar 600 gr.
Step 1. Mix silver chloride, cream of tartar and table salt in enough water to form a dough-like mass.
Step 2. The resulting composition is rubbed onto the object. This mixture is usually used for silvering buttons.
Recipe 4
- silver nitrogen salt 20 g;
- distilled water 10 ml;
- cyanide 50 g;
- water 100 ml.
- cream of tartar.
Step 1. 20 g of silver nitrate salt are dissolved in 100 g of distilled water and a solution of 50 g of potassium cyanide in 100 g of water is added.
Step 2. Both solutions are mixed well and filtered.
Step 3. Separately mix 10 wt. tsp chalk with 1 wt. parts of cream of tartar and the resulting powder is mixed with the appropriate amount of the above filtered solution to obtain a not very thick mass suitable for application to objects.
Step 4. After silvering, the object is washed, dried and polished.
Silver plating by wet method (immersion)
Well-pre-cleaned items are dipped into a liquid prepared according to one of the following recipes:
Recipe 1
- silver plating liquid;
- carbon-silver salt 10 g;
- sodium sulfide salt 100 g;
- water 100 ml
Step 1. Dissolve salts in water with frequent stirring.
Step 2. Drain the saturated solution from the undissolved sediment of carbon-silver salt remaining at the bottom.
Step 3. Objects immersed in this solution are touched with a zinc stick (contact method of silver plating).
Recipe 2
- "Argentin" (liquid for silvering);
- Nitrogen-silver salt 5.5 g;
- Potassium cyanide 60 g;
- Sodium sulfide salt 10 g;
- Ammonia 6 g;
- Exhausted chalk 10 g;
- Water 100 ml.
Recipe 3
- silver chloride 10 g;
- ammonia 70 ml;
- potassium cyanide 40 g;
- crystalline soda 40 g;
- table salt 15 gr.
Step 1. To obtain thicker layers of silver, a mixture of these components is made. Add distilled water so that the total volume is 1 liter.
Step 2. Objects are immersed together with a piece of zinc or placed on a zinc plate.
Recipe 4
- "Argentina";
- silver nitrogen salt 11 g;
- potassium cyanide 60 g;
- exhausted chalk 750 g;
- water 60 gr.
Step 1. A mixture is prepared from these components. Store it in a dark glass vessel.
Step 2. When used, mix one part of the mixture with two parts of rain or distilled water and dip the object intended for silvering into it. Large objects are rubbed with a sponge or rag soaked in this mixture.
After silvering, the objects are rubbed with seasoned chalk and polished with a soft piece of leather.
Silvering when heated
Recipe 1
- cream of tartar powder 600 g;
- table salt 600 gr;
- silver chloride 100 gr.
Step 1. Silver chloride is mixed with cream of tartar and table salt, a little water is added to form a liquid paste.
Step 2. Store in a dark place in a well-sealed dark glass container.
Step 3. Items to be silvered are immersed in a solution of the above components and boiled for 15-20 minutes. For 5 liters of water take 3 tablespoons of the composition for silvering. Silver plating is produced in a copper boiler. The objects are placed in a clay sieve, lowered into the cauldron with strong stirring, after which the object is immediately coated with a thin layer of silver.
Step 4. The resulting silver layer is beautiful and durable, but lacks shine. To add shine, objects removed from the solution are heated to 70-80° in the next solution.
