18 carat gold - what standard is it and how much does 1 gram cost? 18k gold jewelry

Good day! Those who bought jewelry abroad often do not understand what 18 carat gold means: what grade is it and how much precious metal is contained in such an alloy? People from the territory of the former USSR are little familiar with the carat testing system - we have been using the metric system for a long time. The situation is aggravated by the existence of the “diamond carat,” which measures the weight of precious stones. But gold items purchased abroad are often marked with karat marks.

What is the karate system

By the way, a frequently asked question is “How many grams does one carat of gold weigh?” is completely incorrect, since here we are talking exclusively about the content of precious metals. The specified unit of mass is used only to determine the mass of precious stones (it is equal to 0.2 g).

The stamps stamped on imported products contain an indicator of the purity of the alloy and the letter “k”. In the metric system, as mentioned earlier, the maximum possible indicator is 999, its analogue in the carat system is 24.

This is interesting

In ancient times, carob seeds were called carats. They differed little in size, so they were used as a unit of measurement. In the past, different countries had very different carat standards. In the Middle East, a carat weighed 204 milligrams in the metric system.

There was a so-called Arabic carat, it was equal to 223 mg.

And in Egypt it weighed 195 mg. In the UK, until 1988, a carat weighed 205.4 mg, which differed from the carat standard in Europe. This fact drove jewelers to despair.

The metric carat was officially adopted in 1907 at the Congress of Metrologists. Not immediately, but most jewelers appreciated the new standard. Until 1914, it was accepted in most European countries, as well as in the USA and Japan. In 1922, the carat was introduced into the USSR as a measure of weight.

Metric system

More understandable for us, since the numerical designation is the quantitative gold content per 1000 units of the alloy. For example, in one kilogram there is 750 fineness - 750 grams of pure precious metal. This system is used by the State Assay Chamber of the Russian Federation, therefore jewelry is stamped 375, 585, 750, which is a guarantee of its quality.

Imported jewelry, if sold legally in stores, with the designation 14 K, 18 K and others, must be checked by the government service. In addition to the carats, they should have an imprint of 585 or 750 with a woman in a kokoshnik.

Counterfeiting a stamp is a criminal offense, however, when purchasing products abroad, you need to take into account the high probability of fraud. The inscription 14 K or 18 K is very easy to put on jewelry made of any metal. Quite often they can be found on gold-plated products, which they try to sell as full-fledged gold, although their cost is very much lower.

Origin of the word

The breadfruit tree of John, known to people since biblical times, grows in the Mediterranean - Ceratonia capita. Its fruits are consumed as a delicacy, added to immunostimulating complexes, and compote is made from them. But ceratonia also has a non-standard property for plants: it produces seeds, the mass of which is constant and equal to ~0.19 g. Our ancient ancestors noticed this and began to use a measure of weight that refers to the seed of ceratonia (Greek cerátiοn), the carat.

The modern carat (measure of weight) has not changed since then and is 0.2 g.

How to determine carat content

You won’t be able to measure the gold content in jewelry if the sample has worn off and is hard to see at home. The maximum that will be possible is to distinguish a gold alloy from an obvious fake. But if the ring has another standard - metric or spool (it is found on jewelry and luxury items produced before the revolution or immediately after), then you can convert its value into the carat system.

How to convert to the metric system and sample correspondence table

There are two ways to convert carats to thousandths of mass.

1. Calculate. A complex, but universal method that works with unpopular samples. We take 24 carats as 100% and get a carat equal to 4.17% of the total mass. If a product is marked 18K, then in the metric system it is 4.17 x 18 = 75%, that is, 750 fine.
2. Use the correspondence table. I'm including a spool test in case you come across an antique tiara.

Other amounts

The table of ready-made conversions of dollars to rubles contains frequently used amounts of money for transferring between a pair of $ ₽.

Formula for converting metric standards to the carat system

Many people ask the question of how to independently convert a metric sample into a carat sample and vice versa. There is a special formula for this that greatly simplifies the task.

So, this ratio looks like this: 24: 1000 = X: Y, where Y is metric. X - carat.

In order to calculate how many carats a sample represents, you must follow the formula X = 24 * Y: 1000. For example, 585 according to the formula X = 24 * 585: 1000 is 14 carats.

Conversely, metric is calculated as: Y = 1000 * X: 24.

10 carat gold is the most common in the USA; what standard it corresponds to in our country can be easily calculated using the same formula. So, 10 Carat is Y = 1000 * 10: 24 = 416.

Thus, 10 carat gold corresponds to 416 standard, but we do not produce such products.

Correlation of gold samples in different systems.

It is easy to calculate the remaining samples:

• 100% alloy is 24 Karat, which corresponds to 999 fineness;
• 75% of the yellow metal in the alloy is 18 Karat, which is identical to the 750 standard;
• 58.5% in the alloy - 14 Karat and equal to 585;
• 50% in the alloy is 12 Karat and, accordingly, 500 standard;
• 37.5% in the alloy is 9 Carats and, accordingly, 375;
• 33.3% in the alloy is 8 carats and 333 in the metric system.

24 and 18 karat gold belongs to the high-grade group, 12 and 14K jewelry belongs to the middle group, 8 and 9 karat gold belongs to the low-grade group.

Color options for rings of various samples.

A higher percentage of precious metal (or carat value) in jewelry makes it appear more vibrant in color and increases the price.

Legislative regulation

In Russia, all precious metal products with a purity of at least 300 are subject to hallmarking and hallmarking (actually 375, because we do not produce lower-grade gold). The metric value of the sample is applied to the jewelry; it is up to the buyer to convert it into carats.

Reviews

It became interesting, 18 carat gold - what standard? It turned out that it corresponds to the 750 value. I wanted to buy my wife a ring made of this alloy, but then I decided on 585. The sellers assured that high-grade gold would not be suitable for regular wear.

Genady R., Moscow

Artem L. g, Ivanovo

I have been wearing a chain made of this precious metal for a long time. I haven’t noticed any scratches or damage on it, although I try to take care of it. A year ago I took it to the workshop for polishing, the chain still shines like new.

For me, 18 carats denotes undeniable quality. I purchased a stunning black ring from this precious metal. This shade is given by rhodium, a platinum group metal, which also increases strength. The ring is worn every day, I'm happy with everything.

Valeria P. g, Stavropol

A little about this test

750 standard is popular among jewelers and their clients. This is the most successful combination of the purity of a noble metal and ease of use: 999 standard is too soft to be worn constantly. However, a gold content of 75% is sufficient for the product to retain the inherent luster of pure gold.

Composition and properties

As can be understood from the name of the sample, 25% of the mass of our pendant or chain is made up of ligature (foreign metals). Impurities are added to gold primarily because the pure precious metal is extremely sensitive to damage. The 999.9 fine bank bullion can be scratched with a fingernail. This is unacceptable for jewelry that we wear on our bodies, so a ligature is added to gold to increase its wear resistance.

750 gold is common and contains the following additives in different proportions:

• copper (the main alloying component of most alloys);
• silver (also present almost everywhere);
• palladium (added to white gold);
• platinum (rare);
• nickel (rare).

Strength

The price to pay for the prestige of a high-grade alloy and its characteristic shine is the need to wear it carefully. 18K jewelry is easier to break than low-grade analogues.

Alloy shade chart

To understand what shade the alloy will give to gold, you need to look at the original color of the alloying metal. Often there are several additives. Let's look at the popular options for metal “cocktails”:

FAQ

Does white gold occur in nature?

No, white gold does not occur in nature. It is made by hand by adding silver-white metals. The first versions of white gold were created in the 18th century in Germany. However, white gold, a replacement for platinum, was first produced in the 1920s.

How rare is white gold?

White gold is not that rare because it is made from gold, which is often found in free elemental (native) form as well as in minerals.

Platinum, however, is very rare. It is one of the rarest metals in the earth's crust, with an average content of about 5 micrograms per kilogram. With only a few hundred tons produced each year, platinum is one of the major precious metals.

Can regular white gold turn yellow?

Nowadays, almost every piece of white gold jewelry is plated with rhodium (a silvery-white metal), so it will not yellow or tarnish with normal wear. However, this coating must be replaced every few years. Otherwise, the rhodium gradually wears away, revealing the true tone of white gold.

Can hand sanitizer damage white gold jewelry?

Yes, anything containing alcohol can damage white gold jewelry. Because alcohol is corrosive, it can gradually eat away at the metal finish of jewelry. If the sanitizer contains excessive amounts of alcohol, it may cause white gold jewelry to lose its luster more quickly.

White gold contains cheaper alloys, which means the purity (karat) of your gold jewelry is reduced. It is for this reason that white gold has a lower resale value than 22K or 18K yellow gold. If you are buying jewelry for investment purposes, it is better to choose purer, reddish-yellow gold or silver-white platinum.

Ligature of gold

To clearly understand what 18 carat means, you need to know that all gold products use alloys of gold with other metals. In its pure form it is a very soft metal and quickly deforms. To ensure that products made from it keep their shape, other metals are added to the gold mass. They are called alloying. The ligature is the other components of the alloy. Both precious and base metals can be used. Each alloying component gives the alloy certain properties:

1. Copper increases the hardness of the mass, while maintaining malleability, and gives a reddish tint.
2. Cadmium turns white.
3. Zinc lowers the melting point.
4. Nickel imparts hardness and changes the color of the alloy to pale yellow. But unfortunately, this metal can cause allergies in the owner of the jewelry. Nickel is present in greater quantities in the products of Turkish jewelers.
5. Platinum intensely discolors the alloy. For this, 8% of its content in the total mass is sufficient.
6. Palladium increases the melting point and gives gold a light beige color.
7. Silver makes the alloy ductile and malleable.

Section question - answer

What is 18 standard for precious metal?

Expert opinion

Pribrezhny Gennady Valentinovich

Jeweler 6th category

18 standard means the amount of pure gold for the entire alloy. According to the carat calculation system, the number 24 is taken as 100%. It turns out that one carat is equal to 4.17% of the total volume. Then 18K is 4.17 * 24. Accordingly, for a precious metal marked 18K, the pure gold content is 75%.

What does 18krgp sample on a chain mean?

Expert opinion

Grishanov Mikhail Petrovich

Jeweler, director of the Grishanov and Co. workshop

This mark should be read as follows: 18 is the number of carats, that is, of the entire alloy, 75% is pure gold.

Kr is an indication of the carat system.

The letter “p”, coming last, indicates that the number of carats in this alloy is “plumb,” that is, not less than the specified value.

Features of 18 carat gold

An 18-carat gold hallmark corresponds to 750 metric hallmark. As a result, jewelry with this mark indicates that it contains 75% pure gold.

If the product has any standard (metric, spool), then determining the carat content of the material will not be difficult (use the table below).

To determine the specific gravity of pure metal in an alloy, it is enough to use a special formula, according to which 24 carats is taken as 100%. The result is a carat equal to 4.17% of the total mass. Accordingly, if 4.17% is multiplied by 18 carats (in this case) we get 75%, which indicates 750 fineness.

The 18-karat gold standard is considered one of the most sought-after (along with 585). In fact, it is the alloy in which 75% pure gold is most suitable for use in jewelry.

Why exactly the 750th sample? Compared to the 999, items with the 750 stamp are denser and more resistant to wear, so such jewelry can be worn constantly. At the same time, the jewelry will have a beautiful shine. This is why 18k gold jewelry is the best investment.

Typically the alloy is light yellow in color, sometimes with a pinkish tint (depending on the alloy used).

The composition contains additives of 25% of the total weight of the product. The following can be used as impurities:

• copper;
• silver;
• nickel;
• platinum;
• palladium.

Each of the additives allows you to improve the properties of the metal, for example, increase resistance to wear, damage, take care of ductility, etc. The ligature also affects the color of the alloy. The table below will help you compare the composition and shades.

These variants of metal compositions are the most popular, but some others can occasionally be found (usually used to coat products, for example, made of silver).

Brand

In addition to the hallmark, each piece of jewelry must have an imprint of the name of the manufacturer. The name plate is registered by a branch of the Assay Chamber under the Ministry of Finance of the Russian Federation and contains encrypted information about the year of manufacture of the jewelry and the factory.

The 18-carat ring produced by the Russian factory will be marked 750.

What does 18krgp sample on a chain mean?

Traditionally, the purity of gold is measured in British carats.
1 British carat is equal to one 1/24 of the mass of pure substance in the total mass of the alloy. 24 carat gold (24K) is pure, without any impurities. To change the quality characteristics of gold, alloys with various impurities are made for various purposes (for example, to increase hardness). For example, 18 karat gold (18K) means the alloy contains 18 parts gold and 6 parts impurities. The sampling system adopted in the CIS countries differs from the British one and is similar to that adopted in Germany. The sample ranges from 0 to 1000 and shows the gold content in parts per thousand (ppm). Thus, 18-karat gold corresponds to 750 purity. Gold of 999.9 purity is considered “pure”, and this is exactly the purity that it comes in bars. Pure gold is malleable and malleable and scratches easily. Therefore, to increase the wear resistance of jewelry, in addition to gold, copper, nickel, palladium and other alloying elements are added to the alloy. In costume jewelry, gold is used as a covering material. This significantly reduces the cost of the product, while maintaining the appearance of gold jewelry. Depending on the coating method, such products are divided into the following groups:

● gold-plated (gold plated/gold washed/gold finished) Inside the product there is an inexpensive alloy on which 14-karat, 18-karat or 24-karat gold is electroplated. Products with galvanic coating are designated by the English abbreviation GP (Gold plated) or GEP (Gold electroplated).

Source

Price

So, you are holding 18 karat gold in your hands. What kind of test is very clear. All that remains is to figure out the cost. Of course, it depends not only on the carat, but also on the weight, and on the complexity of the work and design. How many grams of gold are in the product - you will understand by the marking. But you shouldn’t rely on this alone when determining the price. The work done in making the jewelry is also taken into account.

For additional comfort, craftsmen can also use special production methods. This allows you to make certain parts of products more flexible and durable. Of course, the better the quality of the decoration, the higher its cost will be. This is justified - after all, you will wear it for a long time, getting great pleasure from it. Well, with proper care, the product will, of course, last for more than one generation. Complex details, special clasps, precious stones - all this, of course, affects the price.

Gold jewelry is most often made using machines. The cost may also increase due to additional hand finishing or engraving. Such operations can be carried out at a variety of prices. Each part may have its own characteristics that make it unique. On average, the price per gram of 18-karat gold today is about 4,500 rubles.

Criterias of choice

First of all, you should make sure that you are buying gold and not gold-plated jewelry. The product must bear the hallmark and mark of the manufacturer - usually they are located on the clasp or on the inside of the jewelry. There are other methods that will help you recognize deception:

• you can try to scratch the object with a thin needle - if the scratch is darker than the surface, it means that another metal is hidden under the layer of gold;
• jewelry that has darkened after several days of wear also indicates a fake;
• Some stores and pawnshops conduct jewelry examinations to order, using special reagents, which gives high accuracy of inspection.

Choose trusted stores for purchase that are ready to provide quality certificates. Remember that 750 gold cannot be too cheap - the average price of one gram starts from 2,500 rubles.

In jewelry stores, you most often find products marked 14 and 18 carats (585 and 750 samples). Let's look at how to choose the best option.

• By appointment . If you are looking for something for everyday wear, pay attention to the 14 K marking. Such jewelry is more durable and can withstand light impacts, scratches and other impacts. Products made from 18-karat gold are positioned as accessories for special occasions. They have a pronounced shine and look impressive, but require careful handling.
• According to the age . If you are buying a gift for a child, it is better to opt for products with low carat. Children do not always handle things carefully and can accidentally damage fragile jewelry.
• By cost. 585 gold is cheaper than 750 gold. The price is also affected by the presence of precious stones, the complexity of the workmanship - unusual details, special fasteners. Most jewelry is made using an automated method, but some designer items require handmade work, so they will be more expensive than others.
• By compatibility. Low grade gold looks duller and its color is not as pure and rich. This is not so noticeable when you are wearing one piece of jewelry, but if you want to put together a set of different pieces, make sure that they are the same carat. For 18K earrings, it is better to choose a pendant or ring with the same marking so that your accessories look organically together.
• According to the presence of allergies . If items marked 10 or 14 karat cause irritation on your skin, you may want to consider switching to 18 karat gold. Such alloys are cleaner, they contain less nickel, which will allow you to wear beautiful accessories without worry. However, if you have very sensitive skin, you will have to look for jewelry with o.

750 gold can have different shades, which is important when choosing.

1. Classic yellow metal is most often used to make wedding rings and luxury watches. This shade goes well with any precious stones and looks impressive on dark skin.
2. Red gold is more resistant to wear due to the large amount of copper in its composition. You can use it to create unusual designer items with complex patterns or use it for everyday decorations.
3. White gold is considered elite and perfectly highlights the beauty of diamonds. However, the composition contains nickel, which can cause allergies.
4. The pink shade is one of the most fashionable; it is preferred by many jewelry houses targeting the luxury segment of the market.
5. Metal with a greenish tint is not often used due to its fragility, but such jewelry looks unusual.
6. Black gold appeared relatively recently, but has already become popular. It is durable and does not lose its shine.

You can choose a shade to match your skin tone or the color scheme that prevails in your wardrobe, so you can easily create a set with gold accessories for any occasion.

When should you buy 18-karat gold?

18K is a good choice if you want jewelry that is fairly clean but not too soft. This alloy, along with 14K gold, is a good compromise between durability and purity.

Of course, 14k gold is harder and more durable.

However, if you are very sensitive to nickel, such items may cause a rash, whereas 18k gold is much less likely to cause an allergic reaction.

It's not a good idea to choose 18K gold for jewelry that you'll wear every day, especially rings and bracelets, which are more likely to get knocked or scratched.

In such cases, 14 or 10 karat gold may be a better option as it is more difficult to bend, break or scratch.

Choose 18K gold for jewelry that you won't wear every day or for jewelry such as necklaces and earrings that are less susceptible to accidental bumps and knocks.

We select jewelry according to several criteria

Emotional buying can lead to negative experiences in the future. To avoid this, you need to evaluate the product you like according to several criteria.

Purpose of the product

It is better to purchase high-grade gold not for daily wear. The ideal choice for this need would be 14 carat jewelry.

Soft 18-karat gold can be a wonderful addition to an evening or holiday look. But even with rare wear, such products should be handled very carefully.

Gold standard 14k

Age

An 18-carat precious metal can be a wonderful gift, but such a gift for a child is not the best solution. Children do not yet understand the real value of many things, and they will not be able to properly care for gold.

How to distinguish gold from gilding

Counterfeiting of jewelry and high-quality items is common. The Assay Office claims that 15% of all products are counterfeited annually. Basically, products made of silver, copper, brass, coated with a thin layer of 24 carat gold are passed off as noble metal. To avoid falling into the trap of scammers, use these tips:

1. Before visiting a store or pawnshop, stock up on a magnifying glass. It will help you better see the mark on the product. This aurum must be marked with the Assay Supervision Inspectorate indicating the sample. Gilded items do not have a hallmark or receive a base metal marker.
2. Pay attention to the edges of the jewelry: gilding is a thin gold coating on an item made of any metal. It tends to wear off over time. If the color is uneven, then the item is not completely gold.
3. Stock up on a magnet. 24 carat metal is diamagnetic and will not attract. But the impurities may include alloys that are attracted by a magnet.
4. Each ingot must have a certificate and passport.

You can have your metal checked without leaving the store. The main thing is not to damage precious products!

Next, we suggest watching an interesting video about how you can check gold for authenticity at home:

Why high purity is not always good

A high standard imposes restrictions on the wearer. It is better to go for things with a carat content below 18 if you:

• you buy jewelry that you want to always wear (for example, to decorate your neck on a mountain hike);
• you are choosing a gift for a child who, due to his age, will not be able to handle it carefully.

Why are low carats bad?

Low-grade gold is inferior in beauty to high-grade gold. It shines duller and looks cheaper. This is not so noticeable when you are wearing one piece of jewelry, but a set of several pieces of different grades will look uneven and give off a low-carat element.

Allergy to nickel.

Nickel is sometimes used in gold alloys. It is found in high concentrations in low purity alloys. Therefore, people with nickel allergies are more sensitive to 10 or 14 karat jewelry, while 18 or 22 karat nickel-containing jewelry does not cause an allergy.

Nickel-containing 18-, 20-, and 22-karat jewelry has an advantage over 14-karat jewelry made with the same metal: purer alloys contain less of it (as a percentage) and are therefore less likely to cause an allergic reaction if you are susceptible to it.

If you are allergic to nickel, 18K gold products will be preferable to 14K gold. Keep in mind that if you are too sensitive, you may need an even higher carat.

If you are prone to allergies but want to purchase 14K jewelry, look for items that do not contain nickel. Typically, such jewelry is labeled “nickel free.”

How to avoid becoming a victim of scammers

You can cheat with gold. I'll tell you about the most common methods:

The chances of running into fake gold are high when purchasing second-hand and are almost minimal in stores and pawn shops.

When buying gold in a store or pawnshop. A guaranteed way to protect yourself from counterfeits is to buy gold in trusted stores, where the products have paper tags indicating the characteristics and manufacturer.

Pay attention to the sample label. If the jewelry was made in Russia, there must also be a name tag.

If you are in doubt about the authenticity of a product, request an inspection. Pawn shops usually inspect jewelry for free in the presence of a potential buyer.

The seller must issue a receipt.

When buying gold at a jewelry shop. A jeweler works officially if he or his company is registered with the Assay Office. The Assay Office is an organization that controls the circulation of precious metals and stones. The jeweler must have a certificate of registration.

Gold marked 18K RGP and how to care for it.

Gold marked 18K RGP and methods of caring for it

Nowadays, buying high-quality gold jewelry is not a problem, since the jewelry market has both cheap jewelry and truly unique pieces. In some companies, a small gold accessory is a status symbol, and absolutely any piece of jewelry can be used as proof of belonging to the company.

To understand the designations and buy jewelry that will not fade after a few days of wear, you need to know the basic methods of making jewelry from gold or gold-plated. The huge amount of foreign goods that have appeared on the jewelry market made of precious metals simply does not make it possible to understand the sample designations, which “tell” how the precious metal was deposited.

The most inexpensive jewelry, such as a chain, ring, necklace, earrings or pendant, made using ultra-thin plating (up to ½ micron) is called flash gold or gold plating. Such jewelry does not have a stamp or mark, since the fragile coating will wear off even with constant wear. If the collection you like does not have an abbreviation, then you need to keep in mind that the period of use of these jewelry is unlikely to be long, therefore, they must be specially cared for.

Much stronger and better quality is hot gold plating or rolling of gold - Rolled Gold . The abbreviation RGP denotes that the product was made using a hot alloy process, whereby the gold "plate" was fused to the base metal. In fact, this is not even gold plating, but galvanic “fusion” with it, so jewelry with this abbreviation retains its external properties for a long time. In addition, if it is indicated that the jewelry is made of 18K RGP - this means that the base metal (brass, copper or other metal) is plated with 18-karat gold (24 units of alloy - 18 units are gold) - this corresponds to the Russian 750 sample

When properly stored, jewelry with 18K RGP , decorated with Swarovski crystals, is magnificent for many years - swarovski crystals retain their transparency and brightness, flowers, hearts or abstract patterns made from them delight their owners. Products must be carefully protected from direct exposure to chlorine-containing agents and rough mechanical friction so that the gold layer retains all its qualities.

How can you clean tarnished gold?

Prepare a solution of hydrogen peroxide, alcohol, warm water, and liquid soap. Immerse the blackened ones

jewelry, leave for at least 20 minutes. Wipe with a soft cloth; Dissolve ammonia, soap or washing powder in warm water.

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Caring for your jewelry

And finally. Gold is a very reliable, strong and durable metal. Anyone who knows 18 carat (what standard it is) most often chooses this option when purchasing jewelry. However, we must not forget about proper care for them. Products must be kept safe and clean.

You should not wear jewelry during rough work or in contact with aggressive chemicals. To protect them from scratches, store each product in a separate box. From time to time, check the fastening of the stones, the strength of the links and fasteners. If you notice the slightest damage, immediately seek help from a jeweler.

In principle, 750 gold is exactly what you need. Especially if you want to settle on a beautiful, reliable and fairly affordable product.

Sources

• https://all-investing.ru/vidy-i-proby-zolota/zoloto-18-karat.html
• https://999proba.com/18-karat-zolota-kakaya-proba/
• https://zhazhdazolota.ru/proby/18-karat
• https://zolotoe-runo-sl.ru/proba/18-karat-zolota-cena.html
• https://TokyoStreet.ru/dragocennye-kamni/18-karatnoe-zoloto.html
• https://VseoMetallah.ru/zoloto/proba/kakoj-probe-zolota-sootvetstvuet-18-karat
• https://DragMag.ru/raznica-mezhdu-14-karatnym-i-18-karatnym-zolotom/
• https://vplate.ru/zoloto/18-karat-skolko-vesit-i-kakoj-probe-sootvetstvuet/
• https://FB.ru/article/270075/karat-zolota—kakaya-proba-yuvelirnyih-izdeliy