How to remove gilding?

In the house of almost every person there are products with a gold dusting - gilding. But certainly not everyone knows that you can remove gold even at home, using a certain procedure and components.

In Russia, in order to cover a product with gold dusting, a precious metal is used, the sample of which is not lower than 750. As a rule, 999 is used. Sometimes you may encounter a 585 sample of spraying. According to experts, in order for gilding to be applied qualitatively, a product made of silver 925 will be required. The applied gold must be at least 42% and the coating thickness at least 2.5 microns. If these conditions are met, gilding will last a maximum period.

If you look at the product, outwardly it can not be distinguished from gold. But gilding is not suitable for everyday wear, because when exposed to mechanical stress, the coating can wear out. Some people mistakenly believe that gilding will be erased in contact with water, but this is not so. Only scratches can destroy the surface. All this suggests that the term of wear depends on careful storage and socks. If a gilt product was purchased at a jewelry store and has the necessary quality certificates, then the jewelry will delight its owner for 2 years or more.

Gilding can be removed from silver and independently. There are two ways to do this:

• chemical;
• electrochemical.

This method requires the presence of "royal vodka" (solvent).The process is delicate because it involves the removal of gilding without dissolving the base. Before starting work, you need to clean the product to a brilliant state. A similar method can be used for coins, when removing from utensils and other products with which to work.

How to act.

• Heated product must be placed in a porcelain cup with a solvent "royal vodka".
• Then the bowl should be heated in a sand bath. It is not necessary to bring to a boil. If you use this processing method, the gilding will begin to be removed slowly.
• Items are removed as soon as dark spots appear on the surface.
• Now the product should be washed in water.
• To remove silver chloride, which appears dark spots, you should briefly immerse objects in an ammonia solution.
• The remaining gilding must be removed with a brush.

This method is relevant for coins. In it, the product is placed in an electrolytic bath and acts as an anode. A copper plate is used as the cathode. The electrolyte is made by adding calcium cyanide solution (7%) to distilled water. When the coins are processed, they are removed from the bath and washed under running water. The remaining gilding can be removed from the metal with a brush.

Gilding can be removed from radio components at home using an electrolyte with nitrate. To work, you will need an electrolyte for the battery, as well as a choice of ammonia, potassium or sodium nitrate. When working with ammonium nitrate, you should use a mayonnaise bucket or any other nylon container (with a lid), the volume of which is about half a liter. In the lid you need to make a hole of 3 mm. 200-300 grams of electrolyte and 100 grams of nitrate are poured into a bucket. The ingredients are mixed until the saltpeter dissolves. Now you can put in the container parts that have been previously cleaned of iron. The bucket is heated in a water bath.

You can boil the pan and place a container in it. While the water is boiling, the parts react with the liquid, as a result of which brown gas will escape through the hole. Work must be done with gloves and a ventilated room. Inhalation of vapor is prohibited. As soon as the reaction has begun, the bucket is removed and put in a cool place. The hissing can continue and even intensify - this is normal. It will last about 30 minutes, after which all the gold will turn into a film on the surface of the liquid. Now you can dilute the solution with water and filter. For this purpose, you can use the matter, folded in several layers. The resulting gold is dried and can be used for further purposes.

There is a safe and simple way that allows you to easily remove the gold coating from telephone SIM cards, processors, microchips, boards. The following should be prepared for work.

• A couple of cans of glass. Alternatively, you can use the bath.
• Thick fabric.
• Fine salt.
• Vinegar. If not, you can replace citric acid and hydrogen peroxide.

Five small tablespoons of salt are placed in a jar, diluted with vinegar, in an amount of 50 ml. Then add 100 ml of peroxide. All ingredients are mixed. Now you can put in a jar of SIM cards. After a minute, the reaction will begin. Every 10 minutes you need to add salt, but not more than 9 teaspoons in total. When the reaction is over, gold particles will remain on the surface, which should be filtered through a cloth.

You can separate the gilding with ordinary pharmacy iodine. The method is relevant for radio components. It will take 1.2 grams of crystalline iodine, 4 grams of potassium iodide, 50 ml of ordinary water. All ingredients are mixed, after which 0.7 ml of nitric acid is added. Now you need to take 10 ml of iodine, you can add radio components. All components are mixed.After 15 minutes, the solution must be drained into another container. In such a short period of time, the solution will have time to dissolve the spraying.

Now it remains to besiege the gilding. To do this, you can use an alkaline solution, for example, sodium sulfite (2 teaspoons), diluted with water in an amount of 20 ml. This mixture is poured into a reagent. It is necessary to pour gradually, as the mixture actively sizzles and sprays. All components are mixed, and when the reaction is over, gold will settle at the bottom.

You can also dissolve gold in sulfuric acid. It will require a concentrated sulfur solution itself, glassware, a 5A power source (minimum). Lead acts as the cathode, and the product itself as the anode. First, sulfuric acid is poured into the dishes. The amount of solution is taken to be minimal, by eye, because then it will need to be diluted. We place the anode, cathode and power source in the liquid and turn on the voltage. A reaction will immediately begin, during which the liquid will darken.

When the current strength begins to decrease, then you can pull out the product. Now it is necessary to dilute sulfuric acid again and filter several times until the solution is no longer cloudy. Products should be placed in water and it is also recommended to rinse, because there will also be gilding. If you need to wash off gilding from gesso, for these purposes you can use a scalpel with a waterproof skin. It allows you to separate the residues from the surface. The top coat of varnish can be carefully removed with a milling cutter or a drill.

When removing gilding, you need to remember your safety. When resorting to electrolysis or another method, you need to work with gloves and in a well-ventilated area. Contact with skin and eye contact must not be allowed. In order not to inhale harmful fumes, wear a respirator. Inside, the use of substances is also prohibited.

Gilding can be obtained from almost any gilded item. If there is a protective coating in the form of varnish on the product, this layer is initially removed with acetone, alcohol or a concentrated solution of sulfuric acid.

In the next video, you will find the removal of gilding from the gilded radio elements of the USSR.