Precious metals are used in the production of valuable coins, jewelry and other expensive products. Sometimes owners of products want to transform them by removing the gilding. How to do it yourself at home? It is in this article that everyone will find the answer to this question, making the task as simple as possible.
Of course, the easiest way to complete this procedure is to turn to specialists and take the jewelry to a special workshop. However, there is not always time for this, and it is difficult to find a good professional in his field, so many people want to carry out the procedure themselves.
You can remove gold plating from silver in one of two ways:
- Chemical.
- Electrochemical.
Jewelry made of gilded silver. Why and what test is applied to silver jewelry?
Jewelry, as well as objects of art, are never made of pure precious metal (as regulated by the periodic system of elements); this is impossible due to the specifics of the metal, since at 0.1% they contain their own oxide - a product of oxidation by atmospheric air .
First of all, the demand for using bimetallic alloys for making jewelry is explained by the characteristics of the metals. Gold and silver are very soft metals that are easily deformed. To reduce this manifestation, alloying (strengthening) metals are added to gold or silver. Let's say copper is most often used for silver, and the same silver is used for gold.
Silver rings with gold plated
In order to reflect on the product the quantitative content of precious metal in relation to the alloying metal, a special test is set. This is a “printed” embossed number on a special belt, which is displayed in an inconspicuous place so as not to spoil the aesthetic appearance of the jewelry.
The Russian jewelry industry uses a metric calculation of the quantitative metal content, which is calculated in milligrams.
Chemical method
In this case, the well-known “aqua regia” will help remove gold from jewelry. This procedure must be carried out extremely carefully, because it is necessary not only to remove the gold layer, but also to preserve the jewelry, leaving the silver without damage. If silver is visible on a precious coin, it must be covered with asphalt.
The method itself includes the following procedure:
- Cleaning coins from all types of contaminants.
- Pour aqua regia into a porcelain cup.
- Warm up the coin a little and immerse it in the liquid.
- Heat the container in a sand bath (do not bring to a boil).
- If dark spots (silver chloride) appear on the coin, it must be removed from the liquid and washed under the tap.
- The product is immersed in an ammonia solution to remove silver chloride.
- Remains of gilding are removed with a brush.
Demand for gold-plated products. Service life of gold-plated jewelry
Products made from pure gold have a high cost, and therefore are not available to everyone. An excellent alternative is presentable, high-quality jewelry made of silver with gold plated. If you don’t look closely, such jewelry may well be mistaken for gold. In addition, they are made of silver, which is also a noble and precious metal.
Detection of a counterfeit can only be done with the help of undercuts or the use of chemicals. But this requires special conditions.
Gold-plated products have their own life, which is associated with wear and tear of the gilding layer. It is also called the leaf layer. The specific durability depends on the composition and thickness of the application. The most durable are jewelry that is sprayed with a layer of liquid alloy of gold and copper. But if you replace copper with cheaper tin, the service life of the coating will be shorter.
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In the USSR, the entire watch industry produced large quantities of wristwatches with yellow cases. But not everyone knew that the case was gold-plated. Over time, the mechanisms have already broken down, but thrifty people feel sorry for throwing them away, so they lie in some vase or box, collecting dust.
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The content of the article:
Perhaps you also have a watch with an amazing Soviet-made mechanism lying around at home.
How to collect watches from the population?
There is one effective way to collect gold-plated watches from the population, which does not require any special expenses. It should be noted that people carry them in such quantities that every watchmaker would envy. In a city with a population of 200-250 thousand inhabitants, one point is capable of collecting more than 200 yellow cases per day.
At any market there is a stall selling small goods made in China. The product can be different: headphones, bicycle parts, calendars in the Geek Porno style, etc. It is necessary to reach an agreement with the owner of the outlet, explaining to him all the benefits of your joint cooperation. In order for the retail outlet to turn into a collection point at the same time, it is necessary to make a bright sign that attracts attention: “Exchange of old watches.” Make small pockets in the same sign where you can place leaflets containing the requirements.
Benefit for the stall owner
1. The sign “Exchange of old watches” attracts the attention of the consumer audience (many become curious about what kind of exchange this is).
2. The owner of a small trading stall attracts new customers who, most likely, would not have bought anything from him if they were not interested in the possibility of exchanging old, out-of-order mechanisms for new ones or another item (thus he will increase sales).
3. It will not be difficult for the seller to give instructions and explanations for the exchange.
People bring watches, if they meet the requirements, then they exchange them for a new product, and we subsequently buy them from the seller at a price of $0.5 to $1. The seller must provide 2 samples - 1 gold-plated case and 1 yellow case that does not have gold in its coating (made in China). In the second case, we refuse the exchange, citing the fact that they are not suitable.
Technological process of gold extraction
People should not be told that the case is gold-plated, but those who know probably understand that the thickness of the coating is small and they are not of particular value. From the case of a men's watch comes 1 gram of 850 gold. Almost any jeweler can buy gold of this standard at a price of $10 per gram.
As for the technological process of extracting precious metal, the following materials and equipment will be needed:
• plastic basin;
• a small saucepan made of heat-resistant glass;
As you can see, the equipment is quite simple and inexpensive. The cases must be processed not one piece at a time, but in batches of 200-300 pieces. It takes about 4 hours to process this amount. Acid consumption is 3-4 liters. The extracted gold is of high purity - 850.
Let's make an economic calculation for this enterprise: Costs: costs for purchasing a batch of 200 cases. x0.5$ = 100$; purchase of 3 liters of acid x $1.5 = $4.5. Total: $100 + $4.5 = $104.5. Income: 200 pcs. / 4 things. = 50 g gold; 50 g x $10 = $500; $500 – $104.5 = $395.5 – your net profit per week. Read more profitable small business ideas here.
Pros and cons of the gold mining business
Pros:
1. This business does not require large amounts of time, with the exception of the time to organize a collection point, make a sign, place an advertisement, and then collect the collected watches from the retail outlet only once a week. There is an opportunity not to leave your main job, but to use this business as an additional source of income.
2. High business profitability with low financial costs.
3. The technology for extracting gold is simple and therefore accessible to everyone.
4. There are no problems with the sale of the finished product.
5. After processing, the mechanisms remain intact and unharmed, which can later be sold to watchmakers.
Minuses:
1. Breathing nitric acid fumes is harmful, but this can be avoided if you follow proper safety precautions.
How to Handle Gilt Silver
Gilded silver has a number of rules for use, which are designed to increase its durability when worn:
- Before going to bed, it is better to put your jewelry in a specially designated box or case.
- When performing work, it is also better to remove jewelry.
These rules are not related to abrasion or deformation, but to the formation of sweat during sleep and work. Sweat destroys gold plating due to its specific composition and acidity pH.
- When working with aggressive cleaning substances, gold-plated jewelry is removed.
- If there is a risk of scratching or harsh impact on gold-plated jewelry, then it is better to refrain from wearing it. Otherwise damage may occur.
In addition, cleaning jewelry is very important, and there are many ways to do it at home. To do this, you can use solutions of ammonia, hydrogen peroxide, vinegar...or simple alcoholic beer. The main thing is to use the recommendations and follow the rules.
Gold plated bracelet
2 best ways - how and how to remove gold plating from silver at home
The following methods are great for removing gold plating yourself at home. They are effective and completely safe if basic safety rules are followed. But at the same time, maximum attention should be paid to safety, since acids are used for sale.
What you need for safety:
- smooth, clean surface;
- latex gloves;
- baking soda on a plate for quick use to “remove” acid that gets on the skin;
- metal or glassware.
Silver earrings with gold plated
Acid method
- Sulfuric acid
Professional method
The professional method excludes the use of acids in their pure form. A professional way to remove gold plating is to use a specific electrolysis method.
Technology for removing gold plating from coins
Electrolysis involves the following manipulations:
- 50 mg is poured into a glass bath. potassium cyanide or an aqueous solution of sulfuric acid - electrolyte.
- Two electrodes are placed inside the dish; professionals use metal plates for this - a negative anode and a positive cathode.
- The decoration is fixed on a conductive cathode.
- A current of up to 15V is supplied to the bath through the anode.
When current passes through the electrolyte, the gold plating will begin to dissolve, and gold will begin to be adsorbed on the cathode. In other words, this is the removal of gilding without dissolving the base.
Important!
Concentrated acids with the addition of mercury can be used as a liquid, but the voltage should be increased to 35V.
Silver coins with gilding
We extract gold with an oxidizing agent
The chemical method is based on the inertness of gold, because it reacts with halogens only when heated. In this case, you need to use the previously described remedy - “royal vodka”. First of all, you need to prepare it by preparing concentrated acids (hydrochloric and nitric) and mixing them in a 3:1 ratio. It is worth noting that its smell is extremely unpleasant, so it is better to act with a respirator. Remember that aqua regia is one of the strongest oxidizing agents.
Important! The solution must be prepared immediately before use. After all, it loses its properties and decomposes, releasing gaseous products.
As for the procedure for extracting gold, the solution simply eats it away from radio components and other objects, as a result of which all metals except gold dissolve. As for the gold, it will float in the liquid like foil that needs to be collected and filtered.
Important! To filter gold you need to use a thick cloth. Medical gauze is not suitable because the holes are too large.
The process itself must be carried out according to plan:
- Procurement of raw materials - you need to rid gold-plated objects as much as possible from others (pull out contacts, bite them, etc.).
- Take a glass, porcelain or stone container.
- Prepare a chemical solution by mixing concentrated acids.
- Pour the liquid into the prepared container and throw the part there.
- Wait until the “chlorine gold” appears.
- Add sodium sulfide to aqua regia to obtain pure gold.
- Collect the gold powder and filter with a thick cloth.
- Wash and dry the gold.
- Melt precious dust into an ingot.
Important! As a result of this method, it is possible to obtain gold, but it will be of low quality and will require additional cleaning, and the loss of the precious metal will be significant.
Reviews
I decided to remove the gold plating from my wedding ring. It is very dear to me, although it is not made of real gold. I made a solution of hydrogen peroxide and hydrochloric acid - my husband gave it to me. I mixed it, threw in the ring, and waited a day. The next day I received a brand new silver ring. Great way. I am preparing the bracelet for cleaning.
Anastasia R., Novgorod
Mark G, Leningrad
I decided to update the chain a little, a gift from Turkey. The gold chain has become patina. I used the hydrolysis method, I read it on the Internet. The acid completely dissolved the gold plating. For 20 years I thought the chain was gold. But at least the method works, I recommend that anyone interested take note. By the way, my wife’s earrings also turned out to be fakes from Turkey.
My mother gave me an old silver ring, covered with gold... well, gilding. Beautiful, but the gilding has peeled off in places. I decided to make myself a simple silver ring. I found many methods on the Internet and chose one - “removing gold plating with citric acid and hydrogen peroxide.” I did everything exactly and now I have a brand new silver ring.
Masha P., Lviv
