18 karat gold: what is it, the properties of the alloy, its cost, marking, use, advantages and disadvantages of the precious metal

Carat system The metric system is often unfamiliar to buyers in our country. In Russia, the metric system is adopted, which looks like a three-digit number imprinted on the surface of a piece of jewelry.

If the product ForeignIt is definitely worth finding out how to read the indicated system of measurement and what the real value of the jewelry is.

18k gold - concept of carat, origin, weight and accepted range

Carat - is a measure of weight equal to 0.2 grams. The name refers to the carob tree, whose seeds had an identical mass and were used to fix the weight of precious metals.

For a long time there was no universally accepted weight category for carats around the world, and there were small errors in both directions. This introduced discrepancies into international trade. The need arose to establish a reference weight unit of measurement for all. Thus the metric carat was born.

Now the carat sampling system is used in America, Canada and a number of other European countries. To indicate the system use abbreviations: K, kt, C, ct.

The carat system uses numbers from 9 to 24 to indicate the purity of the alloy, where 24 is the purest gold.

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18k gold - concept of carat, origin, weight and accepted range
Gold 18k

The carat system of measurement of gold and its correspondence to the metric (proof)

In order to quickly translate the numerical concept of one system into another, it will be convenient to refer to the table:

Metric system999958900750585З75
Carat system242218149
Percent gold content99,995,8%90%75%58,5%37,5%

What is the 18-carat proof?

18K gold equals 750 samples according to the metric system. The purest gold content in jewelry with this marking is 75%.

Conversion of carats to sample and vice versa

There are special formulas that allow you to translate values from one sample system to another.

To convert the carat system to the metric system:

К/24 * 1000

where K is the carat value.

Then, to find the metric value of 18K, substitute the numbers in the formula:

18/24 * 1000 = 750

Accordingly, to translate the metric numerical concept into carat, the formula will be inverse:

24 * М /1000

Gold assay according to GOST in Russia. The controlling body of assaying and branding

The amount of precious metal in golden alloys are controlled by the state. Marking is carried out by the Assay Chamber. On the territory of Russia the following hallmarks are set: Z75, 500, 585, 750, 875, 916, 958, 999. Sometimes the 583 marking is stigma Soviet Union times.

In our country, all jewelry pieces containing at least 30% of pure gold must be pierced and hallmarked.

The structure of the stamp is as follows: first comes the number of the State Assay Control Inspectorate, followed by the hallmark of the assay certificate, and on the right side of it - the numerical marking of the sample.

The cipher indicates the region where the item was hallmarked upon inspection. The mark of the Russian assay certificate looks like an imprint of a woman's head in a kokoshnik.

All information about the gold product will be inscribed inside a figure resembling a spatula.

GOST gold grades in Russia
Gold assays in Russia

All about 750 proof or 18 carats

18 karat gold is an elite alloy that is in great demand. In the jewelry industry, 750 proof is considered to be "gold standard" for its casting qualities.

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985 gold and silver: the characteristics of the highest grade, the correspondence of the carats, the use in various fields, the cost and the nuances of care

Composition and properties of an ideal luxury gold alloy

To understand why 750 gold has gained such high public recognition, it is worth taking a closer look at its characteristics.

Pure gold accounts for 75% of the entire alloy, and the remainder are various impurities that give the precious metal an additional resource of strength. Palladium, copper, nickel, platinum, and silver are used as additives.

By increasing or decreasing the amount of various metals, craftsmen achieve a wide variety of final hues. In the showcases of jewelry boutiques one can see articles made of this precious metal in white, yellow, emerald, purple, pinkish hue.


Gold is an extremely soft metal. Products made of it would be too fragile and sensitive to any mechanical damage.

To compensate for its natural softness, alloys are added to it. In this regard, 750 gold is really the perfect alloy: it contains a higher amount of pure precious metal and a very small percentage of alloying additives that increase strength.

Gold Rings
Gold rings with stones


High-grade gold is very easy to work with and is malleable and flowable. It is used to create items of varying degrees of complexity, from classic engagement rings to filigree chains.

18K gold watches are especially popular and are often presented as the closest competitor to platinum.

Wear resistance

The great advantage of this precious metal over lower grades is its resistance to corrosion and aggressive chemical elements.

Alloy does not lose its shine, does not change color, with proper care always looks presentable.

Shade palette

The hue depends directly on the additives, which also affect some casting characteristics.

Use the table below to determine the ligature of the alloy by the color of the metal.

Variety of shades of gold
Tints of Gold
Pale yellow10%15%
Deep yellow12,5%12,5%
Light green6,3%18,7%

Marking with carats on imported gold

You can see the numerical value of the alloy and the marking of the metal purity measurement system on the imported item. For example, if it bears the imprint "9K", it means it corresponds to Z75 alloy according to the metric system.

Next to the carat value, there is sometimes an indication of the main precious metal - the inscription "gold.

If the carat system is followed by the letter "P", then the marking reads: "indicated number of carats with plumb". The plumb line is the assurance that the item contains at least the designated amount of pure gold.

Read also
999 gold and silver: the properties of the highest grade, the formation of prices in the international market, the use of metals, recommendations for choice and care

For products that do not have an imprint of the letter "P", an error of 0.5 carats to the lower side is permissible. If the letter is indicated, there is no error.

Important: If the imported jewelry has the words "gold-feld" imprinted on it, it means that the precious metal was used only as gilding. If you have gold-plated jewelry from Germany in front of you, you will see the mark "Goldmult" on it.

Cost per gram of 18K gold

The value of any gold alloy depends on the price of the highest sample, which is set by the Central Bank of Russia. This, in turn, is based on the London Stock Exchange rates.

As of 2021, the price of the highest standard varies about 4,200 rubles per gram.

To know the price of any alloy, you need to multiply the price of the highest grade by the required coefficient (e.g., 0.750).

Troy ounce
Gold bars 1 gram

Then you can calculate the value of 18 carats as follows:

4,200 * 0.750 = 3,150 rubles per gram.

Jewelry stores, pawnshops and pawnshops rely on the current price of the precious metal, but set their own price of jewelry. It largely depends on the organization's policy, location, and other markups.

For 18 karat the following data will be relevant:

Price according to the Central Bank of RussiaPrice in jewelry boutiquesPawnshop
3150 rubles.From 4,000 rubles.From 2500 rubles.

Advantages and disadvantages of 18K gold

Not susceptible to corrosion;
Variation in shades;
Suitable for investment;
High cost;
Unresistant to physical and mechanical stress;

Using 18K gold in the jewelry industry

Cost per gram of gold
Gold Jewelry

The 18-carat precious metal is made of:

  • Classic and stone-encrusted rings;
  • Chains;
  • Bracelets;
  • Necklaces;
  • Pendants;
  • Earrings;
  • Hours;

Alloy is also used to create decorative elements, souvenirs, clips, cigarette cases.

The difference between 14 and 18 carats - color, clarity, hardness and durability, markings

The main difference between 14 and 18 carats is the percentage of gold content. For 18 carats, it is 75% of pure precious metal, while for 14 carats it is 58.5%.

Read also
Carat of gold: how much pure gold in 1 carat, the table about the ratio of carat to carat

14K gold is harder because it contains more ligature. If you convert the carat value of this alloy to the metric system, it corresponds to 585 proof.

14 carats have a large palette of colors, depending on the additives products can be white, yellow, scarlet, greenish hue. Copper, nickel, silver and palladium are used as additives.

If you compare the price ratio, the 18-carat precious metal will be more expensive because it contains more pure gold.

The 14-carat metal will be the best choice for everyday wear, as it is less prone to blemishes and accidental scratches.

The difference between 14 and 18 carats - color, clarity, hardness and durability, markings
The difference between 14 and 18 carats

Recommendations before buying an 18K product

Before buying, it is worth bearing in mind that such gold is rather soft. It implies a neat or even festive wear. The most important thing for you to do is to choose a lower-grade precious metal for your everyday jewelry.

Before buying, make sure that the item is really precious and not just gold-plated. This can be done based on a number of recommendations, some of which are also applicable to the purchased jewelry:

  1. First of all, it is worth carefully examining the stigma of the jewelry.
  2. You can try running a needle across the surface of the piece. If the scratch is darker than the base, there is another metal underneath the gilding.
  3. If necessary, ask the seller to confirm the authenticity of the precious metal with assay needles or take the jewelry to a pawnshop for verification.
  4. If a recently purchased piece of jewelry is suddenly darkened, it is a fake.

We choose jewelry according to several criteria

An emotional purchase can lead to negative experiences in the future. To avoid this, you need to evaluate the product you like based on several criteria.

Product designation

High-carat gold is best purchased not for everyday wear. The ideal choice for such a need would be a 14-carat piece of jewelry.

Soft 18-karat gold can be a wonderful addition to an evening or holiday look. But even when worn infrequently, such pieces should be handled with great care.

Gold 14k
Gold 14k


Precious metal Eighteen carats can be a wonderful gift, but it is not the best solution for a child. Children are not yet aware of the real value of many things, and they will not be able to take care of gold properly.

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An older person, on the contrary, will be able to appreciate such a gift.


Fourteen carats are almost half the price of eighteen. At cost will also be influenced by the presence of precious minerals, the complexity of jewelry, uniqueness.

Compatibility with other accessories

One must remember that the colors of 14-carat metal are more faded than 18-carat. This is absolutely not conspicuous if the wearer is wearing a single piece of jewelry. But if there is a desire to assemble a set of different jewelry, it is worth keeping it in a single carat.

By the way, according to jewelry etiquette, it is taboo to wear silver and gold together. However, this rule does not apply to white goldThe color scheme of the gold is the same as that of the silver precious metal. The 18K white gold looks like platinum and together with the silver looks very attractive.


An 18-carat precious metal is less allergenic than lower-allergenic materials. Such pieces are worth considering for people who notice allergic reactions to jewelry of 14 carats and below.

Important: Itching, redness, and burning are likely indications of a nickel allergy. Then the best choice would be platinum pieces or jewelry sold with a "nickel-free" designation.

Gold allergy
Allergic reaction to gold

Question and answer section

What is 18 proof for a precious metal?

Opinion of an expert
Pribrezhny Gennady Valentinovich
6th class jeweler
The 18-th assay means the amount of pure gold for the entire alloy. According to the carat system, the number 24 is taken as 100%. It turns out that one carat equals 4.17% of the entire volume.

Then 18 K is 4.17 * 24. Accordingly, for a precious metal marked 18K, the pure gold content is 75%.

18krgp what does the assay on the chain mean?

Opinion of an expert
Mikhail Petrovich Grishanov
Jeweler, Director of Grishanov & Co.
Such a mark should be read as follows:

18 is the number of carats, that is, of the entire 75% alloy, it is the purest gold.

Read also
Gold assay 583: history of gold from the USSR with a star, composition, properties, the secret of popularity and disappearance, the cost of 1 gram today and use today

Kr is an indication of the carat system.

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

Why is a lot of carats not always a good thing?

Opinion of an expert
Pribrezhny Gennady Valentinovich
6th class jeweler
High carat denotes certain limitations. Such items require careful wear and meticulous care.

For example, while a ring made of low-grade metal can be worn without taking it off, 18K gold will quickly become covered with tiny scratches and lose its original appearance.

Gold Sample Ratio
Gold rings of all kinds

What are the disadvantages of low-grade gold?

Opinion of an expert
Andrey Seleznev
Chemical-technologist of the plant "Krasny Oktyabr" Volgograd
First of all, it is quite allergenic. The high content of impurities can lead to irritation of the skin area, itching, redness.

Low-grade precious metal has no status, bright colors, appearance will always be inferior to the purer material.

Care and rules of treatment of high-carat gold

Observing the following rules will preserve the presentable appearance of the jewelry and help avoid the appearance of various defects:

  • You should remove jewelry before cleaning, cooking, any water procedures, going to the gym;
  • Sunny precious metal should be stored separately from other jewelry, and the place of storage should be dry. The ideal solution is a jewelry box upholstered in a soft cloth or in a jewelry pouch;
  • Your jewelry should be cared for regularly. This can be done at home, but the best solution is to visit a jewelry shop regularly;

Video: How much gold is in 18 carats.


I began to wonder, 18 karat gold - what is the proof? It turned out that it corresponds to 750. I wanted to buy my wife a ring in this alloy, but then I opted for 585. The seller assured me that high-carat gold would not be suitable for regular wear.

Genady R., Moscow
Artem L., Ivanovo

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

For me, 18 karat is an unquestionable quality. I made a wonderful black ring out of this precious metal. Such a hue is given by rhodium, a metal of the platinum group, which also increases the strength. I wear the ring every day, and I am very happy with it.

Valeria P., Stavropol

Jeweler's comment

Molokanov N.M.
Molokanov N.M.
Jeweler, experience in jewelry manufacturing 26 years.
Customers often wonder how much 18 carats of gold is in grams. In fact, the interpretation of such a stamp should be different. The number 18 will mean that in front of the buyer is a piece that is 75% composed of the sun metal.

Each person decides for himself which alloy is better, guided by his own needs. 18-carat precious metal is considered elite, so it is quite expensive. 14-carat gold is more accessible to the general population.
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