Refining is ... Refining gold and platinum at home (ways)

In the modern world, jewelry is very popular. High demand creates demands for quality products. The development of the jewelry industry does not stand still, new ways of processing appear. One of such methods of working with precious metals is refining.

The concept of refining

Refining is a complex process consisting of several stages, as a result of which a precious metal is obtained, maximally purified from foreign impurities. Thanks to cleaning, a higher sample is achieved, which significantly affects the quality of the products and the cost.

Raw materials for refining

The most common raw materials for refining are gold and silver, less often platinum.

Also suitable for the procedure:

• Jewelry scrap;
• Household and technical scrap;
• Coins;
• Schlich and black gold.

Refining is a procedure that is carried out at special plants. The incoming raw materials contain a lot of impurities, upon acceptance it will undergo melting in powerful furnaces. After that, the optimal method of refining is selected, and the process is started.

Despite the complexity, refining is the processing that is available for implementation at home with certain skills and tools.

Tools for refining

For carrying out refining at home it is important to have special equipment:

• Crucible. It is a container in which metal melts, it is capable of withstanding very high temperatures. Purchase of crucible is not difficult, it can be found in specialized stores. That the melting process does not take much time and at this stage there are no difficulties, it is recommended to purchase a furnace for the crucible. Modern installations are implemented with a built-in crucible of different volumes. Important! The crucible must be clean and used only for processing one type of metal. For convenience, it is possible to mark with the type of metal used.
• Tweezers. It should be large and strong. The tweezers serve to transfer zinc to the prepared gold.
• Strong spoke with a thickness of at least 2 mm. It can be steel or titanium. The needle is needed for stirring molten metal, it is sold in any store for jewelers.
• A flask with a volume of at least 0.5 liters. It is designed for boiling, the glass from which it is made, must be refractory.
• Electric tiles and hood. It is important that the spiral in the tile is closed. The hood is needed for covering the crucible. The design is easy to manufacture by yourself: soak asbestos and mix it with gypsum in a 1: 1 ratio.

Gold refining. Consumables

To perform the procedure at home, the following materials will be required:

• Borax - pure and designed for a single use, because its reuse will not purify, but will strongly contaminate the precious metal;
• Nitric acid 65-70%;
• Hydrochloric acid 36-38%;
• Zinc for loosening gold.

The initial stage of refining gold - melting

Where to begin? Refinement is a procedure that requires compliance with rules at all stages. Even a slight deviation from the sequence will not lead to the desired result.

The refining of gold begins with the melting of the metal. It is important to properly prepare the crucible - it must be dry and heated. Calcination of a wet crucible is not allowed to avoid its cracking.

The drill is poured into the crucible and leveled along its bottom. From above is placed the raw material containing gold. The process of heating begins, with increasing temperature, the metal acquires a red tint. At this point, you need to fall asleep on top of the borax and continue heating.

Zinc loosening

There are two popular ways of refining gold at home: using zinc or copper. The simplest method is purification of the precious metal with zinc, it serves as a disintegrant of gold molecules for easy extraction of impurities.

After the appearance of a dense coma of gold floating on the bottom of the crucible, you can start adding zinc. It is placed in the crucible in small portions. Failure to comply with this rule will result in the release of the alloy; Gold and zinc have different melting points (they differ by more than 500 degrees). The heating temperature with the addition of zinc should be constantly increased.

After the zinc is completely dissolved, the alloy should be kneaded and lowered.

Extraction of the alloy from the crucible and its grinding

To continue the refining of gold, the alloy must be removed from the crucible. Extraction is by means of tweezers, which is immersed in water. At this stage, the alloy must have a silvery color.

Then, in a conventional mortar, the resulting ingot is crushed. The process is not difficult - it is very fragile. For best results, the degree of grinding should be maximum.

Gold washing

A flask is mounted above the plate, and the powder obtained is poured into it. There, nitric acid is also added in an amount not exceeding 50 ml.

The reaction follows immediately - the separation of the colored vapor begins. This procedure is desirable to perform in the open air - the steam is very corrosive. After a while (when the reaction weakens) another 50-100 ml of acid is added.

After completion of the reaction, the flask should be slowly heated until a clear vapor appears. Heating stops, and cold water is poured into the flask. The resulting solution must be shaken - the gold particles will settle on the bottom, and the water must be carefully drained, not allowing loss of gold. The procedure is repeated several times, with each subsequent washing the water becomes cleaner, its full transparency indicates the completion of the washing stage.

With a clear implementation of the technology at the bottom of the bulb will remain pure gold, free of extraneous impurities and zinc.

The final stage is getting the gold ingot

To precipitate from gold particles formed into a more familiar gold ingot, you need to melt it and bleach it.

For this, gold flakes are filtered with the help of gauze, in which they are sprinkled with brown. Then the gauze is dried and put in a crucible, covered with a hood. The crucible is placed on the tile - the heating process begins. As a result, a coma of gold is formed, and the gauze smolder. For deeper purification of gold, you can sprinkle it with brown again.

After the gold solidifies completely, it is extracted from the crucible and boiled in a bleach (solution from hydrochloric acid, nitric acid and water) for no more than 5 minutes. Then it is washed in running water.

The result is the gold bar of the highest sample.

Gold refining with copper is identical to the purification process using zinc. The difference is that copper is initially melted, and gold is added to it in small portions. In the process of refining, additional equipment is needed - rollers. They are designed for rolling a finished alloy of copper and gold into thin strips, which should be cut as small as possible. Then these small particles are placed in a flask and go through the same steps: heating, washing, re-melting and forming the finished ingot.

Platinum refining in the home

All platinum metals are rare elements. Most often their refining occurs at special plants. Rare amateur jewelers clean platinum at home.

But if such a need arose - the method of refining is chosen exclusively chemical. Technology is the same as when purifying gold.

Safety rules for refining

The refining of precious metals carried out at home should be carried out in compliance with the safety rules:

• The room in which the refining takes place must be spacious, not cluttered with foreign objects. This is especially true for flammable things.

• It is recommended to use an exhaust design, because chemical evaporation is very toxic, and open windows will provoke a draft that interferes with operation.
• The refining gloves and apron should be used for refining. The body must be completely covered with clothing that is not easily combustible.
• Special glasses are put on eyes, and the mouth and nose are closed by a respirator.
• Hair has the property of absorbing toxic substances, so it is also desirable to close them.

The jewelry industry does not stand still, and today it is possible to obtain precious metals of the highest standard, without the presence of foreign impurities. It is important to understand that gold, obtained by refining at home, is prohibited for sale. In most cases, amateurs simply conduct experiments with raw materials, or carry out refining of gold and platinum, as well as other metals, illegally. Making jewelry from self-made gold is prosecuted by law, refining is performed only at special purification plants or at jewelry enterprises.