How to remove gilding from silver?

Jewelry and valuable coins are made of various precious metals. Sometimes, in order to transform the appearance of a product, it becomes necessary to remove the gilding on silver coins. The answer to the question of how to remove gilding from silver, you will receive in this article.

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How to remove gilding from silver?

Is gilding erased from silver and what should be removed and re-applied? The easiest way to cope with the goal with the help of professionals. To do this, you just need to take your product to a jewelry workshop. But you don’t always want to spend your time looking for a competent and honest specialist, and the question arises of how to remove gilding at home.

Two methods can be used for this procedure:

1. Chemical.
2. Electrochemical.

Important! Before giving preference to a specific technology, check out the list of suitable tools for this matter and their effect on jewelry or coins. So you will avoid an unpleasant situation when the thing will be hopelessly ruined.

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Chemical method

This method involves the removal of gold using “royal vodka”. This is a very delicate operation and the process boils down to removing gilding from silver without damaging the base metal. Therefore, with this method, the parts of the coin on which silver shines through must be previously covered with asphalt.

Important! Before processing, all coins must be cleaned to a shine.

The instruction of this method is reduced to the following actions:

1. Put the warmed coin in a porcelain cup with “royal vodka”.
2. Heat a cup with a coin in a sand bath (not to a boil). With this treatment, the gilding will begin to slowly descend.
3. As soon as the dark spots of the formed silver chloride begin to appear, remove the coins.
4. Rinse thoroughly in water.
5. Immerse the coins in ammonia solution for a short time (to remove silver chloride formations).
6. Remove gilding using a brush.

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Electrochemical method

During electrical processing, the coin is placed in an electrolytic bath (as an anode). The cathode in this case is a copper plate. The electrolyte is made from a 7% solution of potassium cyanide in distilled water. After processing, the coins must be removed from the bath, rinsed under running water, and the remaining gilding removed with a brush.

Important! As in the first method, and in the second, only part of the gilding will be removed.

To remove gilding at home, you must purchase:

• theurea (in the chip store);
• electrolyte for batteries;
• power supply with a changing polarity and voltage;
• distilled water.

To process a coin, follow these steps:

1. Prepare the electrolyte in the proportions provided for this operation.
2. Prepare a glass jar with a tight-fitting lid.
3. Put the coin on the anode.
4. Make a cathode from stainless steel (or titanium).
5. Apply a voltage of 3.5-4 V.

Important! The can should be tightly covered, since hydrogen sulfide will be released during processing, and it is harmful to health.

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Remove gilding from other items

If you want to establish a gold mining business at home, then we will offer you several options for removing precious metal from coating various items.

Sometimes it is required to remove a layer of expensive metal from various gilded objects and get back valuable material.

Important! Gold can be mined from microcircuits, transistors, connectors and other radio components, and even SIM cards.

Why is gold used to cover radio components, and not silver, because in terms of electrical conductivity silver metal has a lower electrical resistivity? The fact is that silver undergoes oxidation over time. Gold has inert properties, which means it does not oxidize when interacting with atmospheric air and does not enter into a chemical reaction with other elements of the Mendeleev system.

Important! Gold is used in the manufacture of electrical contacts, as it is considered more reliable and durable.

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Extraction of gold from radio parts by oxidizing agent

The etching method (chemical) is based on the inertness of gold. Precious metal can react with halogens only when heated. Therefore, in order to dissolve gold, a very strong oxidizing agent is needed. Such is “Tsarist vodka”.

We are preparing “Royal Vodka”

“Tsarist vodka” can be prepared at home. To do this, you must:

• concentrated nitric acid;
• concentrated hydrochloric acid.

It is necessary to take them in a ratio by volume of 1 to 3. “Tsarist vodka” has a strong smell of chlorine and nitrogen dioxide. Self-prepared liquid has no color, but soon acquires an orange color. The interaction of concentrated acids produces a mixture of highly active products that make “Tsarist vodka” one of the most powerful oxidizing agents.

Important! It is better to prepare the mixture immediately before its use, since during storage, aqua regia decomposes with the formation of gaseous products. In addition, during storage, the product loses its oxidizing ability.

The principle of action of the product

The etching process is as follows: the gold-plated elements of the radio components are corroded by acid. As a result, all metals, except inert gold, will dissolve in acid. The precious metal will simply float in the acid solution in the form of a thin gold foil, and to collect it you must carefully filter the solution through the fabric.

Important! Do not use medical gauze for filtering, since it has large holes.

Remove the gilding

Gold extraction is carried out as follows:

1. Carefully separate the gold-plated elements from the rest. For example, pull the contacts out of the connectors, and bite the metal caps with wire cutters and remove. Remember that the procurement of raw materials is a rather time-consuming process.
2. Make a container of glass, stone or porcelain.
3. Now you should prepare “Royal Vodka”. Mix hydrochloric and nitric acids. We get a strong oxidizing agent - nitrosyl chloride, which interacts with gold.
4. Pour the mixture into a container.
5. Throw the part in nitrosyl chloride, wait a bit. Now you should be able to get the so called gold chloride.
6. To isolate pure gold, sodium sulfide (sodium sulfide) must be added to the resulting solution.
7. The result is gold that still needs to be collected. To do this, separate the damaged radio components from the gold test tube.
8. Filter the resulting yellow powder of precious metal from the rest of the solution with a thick cloth.
9. Rinse, dry, alloy the resulting dust into a gold bar.

Important! Obtaining gold by this method has one drawback - a precious metal is mined with losses, as well as with an admixture of other elements, so the obtained gold must be further cleaned.

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We mine gold by electrolysis

For this method you will need:

• container made of heat-resistant glass or porcelain;
• 50 g of potassium cyanide;
• 1 liter of distilled water;
• as a cathode, iron or silver plates.

Proceed as follows:

1. Suspended gold-plated objects are suspended to the positive electrode (anode).
2. Dip in the bath with the prepared solution.
3. Turn on the DC voltage from 12 to 15 V.

Important! At a voltage of 12-15 volts, gold will deposit on the cathode with a film.At higher - in the form of a sponge.

4. Scraped gold deposited at the cathode.

Important! Good results can be obtained if concentrated sulfuric acid is used as the electrolyte, and a lead plate for the cathode. The voltage should be 3-4 V.

Compared with the chemical, the electrolytic method of removing gilding is simpler and more effective, since it gives a greater amount of gold to be removed.

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Helpful hints:

• Gold can also be removed from other gilded objects (watches, home decoration, etc.), but if the objects are varnished, rinse off the protective layer with alcohol, ether (acetone) or immerse in concentrated sulfuric acid, which will remove the organic parts of the varnish.
• More details about radio components and the gold content in them can be found in the passports for radio equipment.
• All work with chemicals should be carried out with caution, using protective equipment.

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We hope that thanks to our advice and the information received, you will be more respectful of things containing gold, and if necessary you can get it at home.