Processing rough diamonds into polished diamonds is not difficult from a production technology point of view, but it is nevertheless extremely difficult human labor. The basic operations have remained virtually unchanged for several hundred years and are performed manually. However, all of them are constantly being improved in the direction of increasing the productivity of diamond processing and the quality of manufactured diamonds, as well as in the direction of creating new shapes and types of cuts.

When processing diamonds, you must rely on special knowledge, have patience, perseverance, and under no circumstances rush into making a decision regarding a particular future diamond. The decision on how a diamond should be cut is made based on its natural shape, taking into account the stone's internal crystal structure, inclusions and flaws, so diamond production You constantly have to make a choice between the largest possible size and the highest possible quality of diamond. There are no strict rules on this matter. Nevertheless, despite all the difficulties, a perfectly cut diamond must emerge from the hands of the cutter.

The technology of processing diamonds into polished diamonds means the sequential performance of certain operations with diamond crystals. Such operations include: pre-production research of diamond crystals, their marking, sawing(splitting), sanding(rough peeling) stripping(turning), cut, polishing, flushing And grade.

As scientific and technological progress develops and cutting equipment improves, the content of the operations themselves may change, but their essence and name will most likely remain the same. For now, the main technological principle remains that diamonds are processed only with diamonds, although laser machines have long been introduced into the practice of their processing, which perform some operations more efficiently.

Pre-production analysis carried out to determine the technological direction of diamond processing. Here, sorting is carried out according to the shape of future diamonds, crystals are determined for sawing (single or multiple), splitting or polishing; the features of each crystal are determined, stressed and defective crystals are identified, the nature and location of natural defects, etc. Essentially, at the pre-production analysis stage, a forecast is made of the weight of the finished diamond, the main geometric parameters, evaluation characteristics and cost of the future diamond.

Today, new generation cutting factories use modern technologies in the analysis, optimization and planning of diamond cutting. Computer systems for simulating diamond cutting help the technologist (cutter) to assess the possibility of a diamond and plan its processing. The system provides an instant analysis of the rough diamond and shows how it can be turned into the optimal diamond. Next, after choosing a cutting method (shape), you can set parameters for applying laser markings. The size of a diamond is an extremely important factor in the value and cost of the finished stone, so weight loss at each stage of cutting and polishing is carefully monitored by the technologist (cutter) who controls the processing process.

At marking lines are applied to the crystal, forming a sawing or splitting plane, and in the case of polishing, the plane of the diamond platform is applied. The main goal of marking is to obtain a diamond or combination of diamonds with the maximum value.

In progress sawing or splitting, the diamond crystal is divided into parts, which, according to the plan of the technologist or marker, determine the optimal use of rough diamonds. This often removes natural defects in the diamond, which increases the value of future diamonds. The technological process itself is quite labor-intensive and consists of several sequential operations that require attention and exceptional accuracy. Further work with the resulting semi-finished products and the final yield of diamonds largely depend on how these operations are performed.

Process sanding (rough peeling) is the removal of excess mass of the crystal. This operation is used when processing irregularly shaped crystals and crystal fragments when it is impossible or impractical to saw or split them. As a result of grinding, a workpiece (semi-finished product) is obtained, suitable for use in the operations of preliminary application of edges and roughing. Typically, this operation begins immediately after pre-production analysis, but can also be performed after sawing or splitting crystals of complex shapes.

Rip off Diamond processing is considered one of the most critical operations in the entire technological cycle of diamond production, on which the utilization rate of rough diamonds largely depends. During roughening (grinding), the basic shape of the future diamond is made. Peeling can be carried out in one stage or in several, when it is divided into roughing and finishing.

Cut quality - This is one of the most significant parameters when evaluating a diamond. Diamond cut, i.e. Applying facets at a certain angle relative to each other allows the diamond to refract light rays as much as possible. The bevel is obtained by friction against a grinding wheel (diamond disk), and linseed oil is used as a grinding agent. First, a large smooth facet is removed at the top of the stone - the platform. Then the main edges are applied from below and this cone-shaped part is called the pavilion. Next, the facets on the top are sharpened - this is the crown. Then additional edges are applied on the pavilion, then again on the crown. Each facet requires adherence to exact dimensions, shape and angle. The stone is also surrounded by a faceted belt - a girdle, and below, in the very bottom of the pavilion, a culet (spike) appears, parallel to the platform. The cutting itself is the application of a platform, edges and wedges to a turned workpiece in a certain sequence, observing the basic parameters for cutting.

Diamond cutting - applying the main edges of the bottom

Operations cuts And polishing are combined and carried out on the same cutting disk, the parts of which are carved with diamond powder (paste) of different sizes. Cutting itself is the application of a platform, edges and wedges to a turned workpiece in a certain sequence, observing the basic parameters for cutting. Polishing ensures a high surface clarity of the diamond and, therefore, a high light reflectance from its surface. Cutting and polishing operations are the most labor-intensive and critical in the overall technological process of diamond manufacturing.

Diamond cutting and polishing

Flushing diamonds is the final stage in the production cycle of their manufacture. The purpose of rinsing is to remove manufacturing dirt and oils from the surface of the diamond. Flushing consists of several sequential operations. In this case, a washing solution based on concentrated sulfuric acid with the addition of a certain amount of potassium nitrate, distilled water and pure alcohol is used. The diamonds are first boiled in a cleaning solution that removes remaining oils and dirt, and then they are rinsed repeatedly in distilled water and dried with alcohol. Only then do diamonds turn out clean and acquire their marketable appearance.

Further diamond appraisal consists of determining their mass in carats, sorting by size and weight groups and cut shape, determining the color group and defect group and the quality of finishing in accordance with the Russian industry classification or one of the international classifications. The assessment is carried out by experts.

I don't think it's worth talking about how hard a diamond is. Everyone already knows that diamond is the hardest substance found in nature. But at the same time, everyone knows that diamonds are cut, polished, faceted, and polished. How? What can handle this super hard substance? Only the diamond itself.

The fact that if you rub one rough diamond against another, their edges are polished, and the brilliance of both increases, was noticed in ancient India. In Europe, diamond cutting began much later, in the 14th-15th centuries. In the middle of the 15th century, the jeweler of the Duke of Burgundy, Ludwig van Berkem, first cut a diamond, which later received the name “Sancy”.

In the 17th century, they learned to saw diamonds. The first saws were iron wire, the surface of which was carved (saturated) with diamond powder. Sawing large diamonds took a long time; for example, the Regent diamond, which weighed 410 carats, took about two years to saw, consuming a huge amount of diamond powder.

Nowadays, diamonds are cut on special machines using rapidly rotating bronze disks 0.05-0.07 mm thick. A suspension of diamond powder is fed onto the discs. Modern installations provide for the use of ultrasonic, electrical discharge, laser and other types of processing to intensify diamond cutting.

The most difficult and responsible process in making diamonds from diamonds is cutting. It is produced using a rapidly rotating disk made of copper alloy, into which small diamonds are pressed, or a cast iron disk, into the surface of which diamond powder diluted in burdock or olive oil is rubbed.

At the same time, the shape of the stone and the arrangement of the faces in it are made in such a way that the incident light does not pass through the stone, but, having undergone complete reflection from the inner surfaces of the faces, returns back, providing a “play” of light.

Diamond cutting is an extremely complex and labor-intensive process. Large stones take months to cut, while unique ones take several years. The weight of the diamond from this operation is reduced by half or three times, and its value increases proportionally.

Therefore, before starting to cut large diamonds, they carefully calculate the shape of the future diamond, which will provide the best “game” and allow maximum preservation of the mass of the original stone. Nowadays, computers are used for this purpose, which make the task as easy as possible.

It would seem that a diamond is a flawless stone. But it also has its drawbacks. It is chemically active towards iron and nickel. At elevated temperatures, it forms interstitial solutions with them and is destroyed. That is, it is impossible to cut steel with a diamond at high speed.

Diamond is powerless even against soft iron. As the iron heats up during the cutting process, it begins to dissolve carbon in large quantities. Thus, it “eats” the hardest material in the world.

However, any disadvantage can be turned into an advantage. This simple chemical reaction can be used to process diamonds. This property of an impregnable diamond allows it to be easily cut with hot steel wire.

If you apply an iron cutter heated to 1000°C to a diamond, it will begin to dissolve carbon, plunging deep into the diamond at a speed of up to 0.3 mm per hour. By changing the shape of the cutter head, it is possible to make complex parts from diamonds, for example, bushings, gears and other complex-shaped products that cannot be made in any other way.

In principle, this article could be written on a diamond, if only there were a diamond of the appropriate size and a red-hot nail!

Alexander Saitov

Original post and comments at

Yes, yes, dear reader. “Zvezdochka” is not only known for steamships. Since the beginning of the 2000s, the company has launched production of cutting rough diamonds into polished diamonds. As many probably know, a diamond, with all its other technical advantages, only becomes “the girl’s best friend” when it turns into a diamond. Today's photo report tells us about the path he will have to go through.

It all starts... You guessed it with a hanger. Third-party visitors who have passed the hard materials processing station (as cutting is officially called) are asked to put on a robe and are assigned at least two accompanying persons: a workshop worker who acts as a tour guide and an employee of the economic security department. Trust, as they say, but verify.

Now we are ready to get acquainted with the workshop. The first point on the route is a storage room for raw materials.

This is where the raw materials—uncut diamonds—come. Here they are processed: they are counted, weighed, checked for compliance with shipping documents, each stone is entered into an electronic accounting database and a unique route map is written out for each stone. In this route map, folded into an envelope, the diamond will travel through the areas.

This is done using a computer markup system. The installation scans the diamond and forms its three-dimensional digital model. Using this model, the technologist will decide how many diamonds will come out of a particular stone and what shape they will have. The principle of combining the value of the future diamond and minimizing waste is at the forefront. The program not only allows you to visualize the diamonds hidden in the diamond, but also gives their approximate value. The classic KR-57 cut usually has the highest cost. Unfortunately, not every natural stone allows you to achieve exactly this shape with maximum use of raw materials.
The cost of this diamond placer is $3,560.

This stone will produce one diamond, but larger. Its cost will be just under three thousand dollars.

And of this - two, but smaller and, accordingly, for a more modest pocket.

Before leaving the site, the stones are glued onto special mandrels for subsequent processing. This rack is heated in an oven so that the glue holds the diamonds securely.

From the UZTTS the stones go to the sawing and peeling area. In the old days, sawing stone was done mechanically using a bronze disc coated with diamond.

Today, the majority of sawing is done with a laser. The installation operator has the ability to visually monitor the process.

Laser cutting, firstly, is faster. The sawing process, depending on the size of the stone, can take from five minutes to half an hour. Secondly, the laser cut thickness is only 2 microns, which significantly saves rough diamonds.

However, some stones that have high internal stress are dangerous to cut with a laser. And then sawing is carried out the old fashioned way - with a bronze disk.

After sawing, the diamonds, each of which is packed in a separate sheet-envelope with a bar code, a list of all operations carried out with the stone, the names of each of the workers whose hands touched the stone, and other information, are sent to the cutting department. This is where the diamond will turn into a diamond.

Diamond cutting is carried out on a rotating cast iron disc coated with diamond. When exposed to the mechanical action of a grinding disc, carbon changes its structure. A thin graphite film is formed on the crystal, which wears off, bringing the diamond to the desired shape.

The diamond is fixed into the seat of a special hand-held device - a collet.

Using adjusting screws, the cutter changes the position of the stone in the collet so that the diamond rests on the disk at the desired angle. This is how a shapeless stone acquires a platform, edges and wedges.

It also happens that the stone falls out of the collet mount. The rotating disk can send it on a “journey” around the area. Then the command “loss” is heard and the unlucky cutter goes in search of the lost diamond. Despite the fact that each cutter's place is equipped with special stone catchers, it happened that the search took a very long time.

In general, when the signal “loss” is signaled, the entire production turns into a “submarine”, from which, as you know, you can’t escape. Exit outside the site is stopped while searching for the lost stone. In the entire history of the work, only one diamond was considered completely lost. But he was found too. Having flown out from the cutter’s disk, the stone “stuck” to the wall, where it was discovered only a few years later.

When grading, cut stones are compared to these standards.

The color and imperfections of a stone are almost the decisive factors in its price. The price of stones of similar weight and cut, but different in color, can differ significantly.

From the evaluation site, the diamond, through another storeroom, is sent far away - to the Smolensk Gemological Center. In Smolensk, the diamond will receive a certificate and turn into a commodity. It can be legally sold, given as a gift, passed on by inheritance, or simply “languished” over it, like Pushkin’s Koschey over gold.

The cost of this certified diamond is about one and a half million rubles.

All movements of stones outside the workshop are carried out by special communications convoys. Inside the workshop, control over the movement of stones is carried out by the economic security department of the enterprise security service. The accounting of stones is organized in such a way that even after many years it is possible to completely restore the history of each of them. Where it was mined, how and by whom it was purchased for processing, who and when touched this stone, what manipulations were performed with it, where at a particular point in time this stone was located while it was at the factory.

Jewelry production is technologically closely related to cutting. Gold, silver, rings, earrings, rings, pendants... Yes, yes. We have them too.

The production of serial jewelry begins with waxing.

In special rubber molds, the worker casts wax “prototypes” of future rings or earring parts. A casting mold is assembled from these wax blanks. Here it is called “herringbone”. The blanks are glued to the wax rod one to one, like branches on a Christmas tree. The collected wax tree is sent to the foundry area. Here it is filled with a molding mixture, mainly consisting of gypsum with special additives, and placed in the oven for several hours. The casting mold - flask - hardens, the wax is melted out of it, leaving an empty space of the desired shape.

Molds for custom-made piece jewelry or new designs are made on a special milling machine. Here the machine cuts them out of wax according to the loaded 3D models. The customer has the opportunity to “touch” the product before it is made in metal.

At the next stage, the plaster mold will be filled with gold alloy. Precisely an alloy. Alloying additives are introduced into gold of the 999th standard, bringing it to the “commercial” 585th standard.

Everything happens in this foundry furnace.

Ship steel comes to the plant in sheets, and jewelry gold comes in kilogram bars. It looks like a pure chocolate bar.

An ingot is a practical form for storing and transporting gold, but handling ingots is inconvenient. On this machine, gold entering jewelry production is rolled into strips into gold foil.

Diamond is a natural mineral that is carbon with an allotropic crystal lattice. Due to the peculiarities of its molecular structure, it is an extremely hard material that can be stored indefinitely.

The chemical composition of diamond can be changed under the influence of various factors: high temperature, pressure and/or vacuum. As a result of their action, diamond turns into another chemical element - graphite, which has a different composition of qualitative characteristics.

Diamonds are obtained through natural mining and artificial mining. In the second method, the chemical element graphite is exposed to high temperature and pressure. The graphite material changes its molecular structure and turns into diamond raw material, acquiring characteristic strength properties.

The resulting raw material requires additional processing before further use. The factor of increased diamond hardness requires a special approach to the methods of its implementation.

Story

The history of diamond mining is extremely young. This is explained by the complexity of searching and extracting the mineral, as well as the difficulties associated with its processing. The technology of processing the described material using another diamond began to gain popularity only in the 14th-15th centuries AD. Until this time, this method was used only by ancient Indian masters, who carefully kept the secrets of the technology.

On the territory of Russia, the development of mineral deposits and the development of technologies for its processing took on an industrial scale only in the second half of the 19th century. Today in Siberia, work is underway to extract this mineral from mines that are on the list of the largest in the world. At the same time, all types of diamond processing have been mastered.

Processing Features

The processing technology and the set of technical devices suitable for this are determined by the name of the final purpose for which the processed diamond will be used.

The characteristics of diamond necessitate its use in various technological systems, tools and devices. For example, a small diamond fraction - crumbs - is used as a coating that covers the working surfaces of any cutting devices. Diamond spraying is used for application on cutting discs, saws, and tapes intended for cutting metal, stone, concrete, ceramics and other materials.

Despite the resistance of diamond to a wide range of destructive loads, it is a brittle material. The use of impact-pressing technology makes it possible to grind diamonds into crumbs. The mineral is crushed using a hydraulic press (this processing option is rarely applicable).

Roll grinding technology is more widely used. As part of this process, raw materials are fed through a conveyor into a special chamber in which cylindrical rollers in contact with each other rotate. Passing between them, the rough diamonds crumble. Taking into account the strength coefficient of diamond, several blocks with rotating rollers with different gap sizes between them are used on the conveyor. This allows you to reduce the load on the mechanism, since stage-by-stage crushing is carried out according to the principle from larger to smaller.

The working surface of the rollers is coated with diamond coating, since no other material is able to withstand this load in such an effective equivalent.

The dimensional parameters of the crumb fraction are determined by the name of the final purpose for which it will be used. Diamond chips of a coarser grain size are used for rough processing of materials with a high strength coefficient: ceramics, granite, porcelain stoneware. For example, large chips are used as a cutting element applied to the working edge of circular bits designed for cutting round holes in hard materials: ceramic tiles, concrete, granite slabs and others.

Diamond chips of finer grain size are used for fine processing of certain materials. As part of this processing, materials are cleaned, ground, and polished. Polishing is done with a special paste based on diamond dust. Obtaining diamond chips of different grain sizes is achieved by crushing and subsequent sifting.

Passing crushed diamond through mesh panels with different mesh sizes makes it possible to obtain fractions of a fixed diameter.

The process of obtaining diamond materials suitable for industrial use is a more labor-intensive procedure than impact-pressing technology. These materials are used, for example, circles for cutting glass, tips of lathe cutters and others. They are elements consisting entirely of diamond mass. The production of such additions involves production procedures associated with resource costs and the use of several processing technologies simultaneously.

The strength properties of diamond significantly complicate the production of parts that place high demands on dimensional parameters and shape accuracy.

The only material that can be used to effectively process rough diamonds is the diamond itself.

The correct combination of factors affecting the processing tool and the material being processed allows processing to be performed as efficiently as possible. For example, in some cases, the workpiece is heated within a medium temperature range, and the temperature of the processing tool is kept in the low thermal range. In this case, the heated workpiece can be processed, and the percentage of tool wear is reduced.

The use of this method is due to the properties of diamond, which it acquires under the influence of high temperatures. The higher the temperature, the lower the strength coefficient of the mineral.

How to make a split?

Another method of diamond processing is hot iron processing. This mineral is capable of entering into a chemical reaction with metal heated to high temperatures. The hot iron begins to absorb the carbon component of the diamond. At the point of contact between the hot metal and the mineral, the latter melts at the molecular level.

This method has low production efficiency, however, only with its help can one achieve certain results in the processing of diamond material.

The hot steel method is used when it is necessary to saw a large volume of raw materials with a minimum waste coefficient. This method uses hot steel wire driven by rotating shafts. In this case, the cutting line is as thin as possible, and the loss of the main raw material is kept to a minimum.

Using the hot sawing method, you can only perform manipulations aimed at general processing. Detailed cutting is performed using more complex grinding technologies. This method also uses hot drilling technology. In this case, the drilling steel element is also heated to high temperatures. The effectiveness of the method is also increased due to the heating of both parts as a result of friction against each other.

Diamond drilling is used to perform roughing. Holes of the required diameter are drilled along the split line of the workpiece. Special anchor expanders are immersed in them. The technology allows you to control the expansion of anchors one by one or simultaneously. Thanks to this, it becomes possible to perform controlled splitting of the workpiece along a given line.

The angle at which the holes are drilled plays a key role in the effectiveness of the method. Any deviation from the specified values ​​may lead to a violation of the splitting accuracy.

How do you polish a diamond?

The main direction in processing technologies for this mineral is its grinding. Through this procedure, diamonds acquire their final shape, and in some cases turn into gemstones.

When making diamonds, craftsmen resort to step-by-step processing methods. The rough workpiece is cleaned of impurities of other minerals, if any. Then rough sawing is carried out, thanks to which the basic shape of the future product is formed. After this, cutting begins.

To grind diamond minerals, devices are used that are equipped with special attachments - disks or plates that have a thickness, shape and material that corresponds to the name of the procedure being performed. Fractions of diamond chips of various diameters are applied to the working surfaces of these nozzles.

If cutting is carried out to obtain a precious stone - a diamond, then many attachments with a wide range of dimensional parameters are used. The plates or disks with the largest diameter diamond chips are used first. As the process progresses, the grain size of the nozzles decreases. Final polishing is carried out using diamond nanoparticles.

As one modern song says: “Diamonds are a girl’s best friend.” There is probably no person who can argue with such a statement. A jewelry factory that creates works of art from precious metals with diamonds encrusted in them is faced with the difficult task of processing diamonds, because a diamond is nothing more than a diamond that has been given the necessary cut using special technologies. And this task is not at all easy, because diamonds are considered the hardest stones in the world.

How is a diamond processed?
Diamond processing is based on two factors. The first is its structure, the second is the processing method. Speaking about the structure of diamond, it should be noted that diamond is carbon that has a high degree of crystallization. The carbon atoms that make up a diamond always create a geometric arrangement that allows pieces to be broken off parallel to the planes that the atoms create. After this kind of procedure, the surface becomes smoother. Surprisingly, the tool for processing a diamond is a diamond, or more precisely, its chipped pieces. A depression is made on one side of the crystal. A thin incisor is placed there. After hitting the cutter, another piece breaks off from the crystal. During diamond processing, the direction of this processing should not change. The crystal is sawed using special metal discs coated with diamond dust and lubricant. It turns out that with the help of diamonds we process diamond. Processing the hardest substance on Earth is a long and labor-intensive process. Only highly qualified specialists who have studied this craft for more than one year are allowed to perform such work. And the training will end with the person becoming only a trainee for many years. It won’t be long before he starts processing diamonds on his own.
Diamond (from the French brillant - brilliant, sparkling) is a diamond that has been given a special shape through processing, maximizing its natural brilliance. Diamonds are graded using the “4 Cs” system: cut, clarity, color and carat, which allows us to determine how close the stone is to perfection.

The main thing in assessing the cut of a stone is its quality: how geometrically accurate and proportional the edges are. The ideal cut is coded with the letter “A”, then in descending order of quality. Clarity is the most significant indicator of the quality of diamonds: it is expressed in the presence or absence of stone defects or foreign inclusions. A perfect diamond, without flaws, is called a pure diamond. By color, diamonds are divided into traditional (colorless and all shades of yellow) and fancy (pink, blue, indigo, green). The weight of diamonds is measured in carats (1 carat equals 0.2 grams).
The first forms of processing were quite primitive: they ground down one of the edges and polished it. In 1465, the court jeweler of the Duke of Burgundy, Ludwig van Berkem, first produced a rose-shaped cut. Over the centuries, jewelers have developed the perfect diamond cut, so that the light in the diamond is completely internally reflected. In 1961, Arpad Neji, who worked in this direction for 13 years, developed a new diamond cut - profile (“princess”). In recent years, this particular form of diamond has become very popular.