How are karat and gold purity related?

If you are planning to buy gold jewelry in foreign online stores, then the first thing you should pay attention to is the number of carats. What do carats mean?

The number of carats indicates how many parts of the precious metal the product consists of, with a maximum of 24.

For example, in a 14-karat bracelet, the alloy consists of 14 parts of pure gold out of a possible 24, and the remaining 10 parts include other metals: copper, nickel or zinc.

Thus, a 22 karat gold chain will contain 22 parts pure gold and only 2 parts other metals.

The seal and its meaning.

Carats are most often indicated on gold jewelry by a number with the addition of a name indicated by the symbols: K, k, ct, CT, or CT.

For example, a ring “10 ct” and “10 karat” mean the same thing - the product contains 10 karats of gold.

Instead of carats, you sometimes see purity numbers imprinted on jewelry as percentages or parts per thousand. For example, the stamp "999" (or ".999") means that the alloy is 99.9% pure gold and this corresponds to 24K.

Sometimes, you may see the letter "P" printed next to the carat number. For example, the marking “18 KR” means that the gold content of the product is guaranteed to be at least 18 carats.

If you have already purchased a product in a foreign online store or auction and there are no carat marks on it, then if you wish, you can check it for purity.

To do this, you can contact jewelers.

A large number of specialists provide such services for an additional fee.

Typically, they determine the purity of a gold item using acid to determine the exact number of carats.

How much does 1 carat weigh when measuring the weight of gemstones?

According to the certificate, the carat weight is equivalent to 200 mg (0.2 grams). Moreover, in most countries (including Russia), the carat cannot have a fractional part, and the weight of the raw material or product is indicated by an integer.

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Carat standards.

The most popular carat numbers for gold jewelry are 10, 14, 18, 20 and 22 carats. (It's rare to see 24K jewelry because pure gold is too soft.)

It is important to remember that jewelry with a purity of less than 10 carats is not technically considered gold in the United States. Keep in mind that unless your gold jewelry is about (as in "14 kiloponds"), the exact number of carats may vary slightly from what is stated on the stamp.

In the US, the tolerance is +/- 0.5 carats. This means that your 14 karat gold piece may actually be 13.5 karats.

How many grams are in one carat of jewelry?

You can determine the weight of a gem yourself; there are several ways to do this.

Diameter to weight ratio

You can find out the weight by diameter if you are dealing with round gems. A special table shows the ratio of the mass of the stone and its diameter. For example, 1 carat is how much in diameter:

• 1 millimeter – 0.005 carats;
• 2 mm – 0.003;
• 3 mm – 0.1;
• 4 mm – 0.25;
• 5 mm – 0.5.

The larger the diameter of the gem, the higher its mass. Here you should also take into account the type of cut, since an oval cut will require less material than a classic round cut.

Calculation of gem weight relative to cut

In the absence of scales, minerals are measured using their length, width and cut. Here are some excerpts from the table for determining weight by cut:

1. Round. The squared diameter is multiplied by the height of the stone, by its density and a coefficient of 0.0018.
2. Marquis. Length multiplied by width, height, density and a factor of 0.0016.
3. Round cabochon. The diameter is multiplied by the density of the stone and a coefficient of 0.00259.

Attention! When using this method, you must always take into account possible defects and add 3-6% of the resulting mass to the convexity of the stone.

What is the difference between large and small carat values?

Generally, the lower the karat and less pure gold metal in your jewelry, the heavier and more durable it will be.

The disadvantage is that the less pure gold there is in the alloy, the less similar it will be to gold.

In addition, the smaller the carat, the more nickel the alloy contains in its composition.

For people who are allergic to nickel, low karat gold jewelry may cause breakouts and skin irritation.

Higher carat values, on the other hand, look better because... contain more gold.

But pure gold is a rather soft metal, so products made from this alloy are more easily scratched.

The most popular are 14 and 18 carat jewelry, as these carat levels provide a good balance of durability, quality and price without causing allergic reactions.

Legislative regulation

At the state level, there is strict control over enterprises working with precious metals. All released products must have a special mark confirming its quality. Even if the deviations in the declared amount of gold are insignificant, entire batches of finished products are sent for processing.

In Russia, the quality control function is performed by the Assay Office. The stamp on products made in the Russian Federation contains a three-digit designation of the sample and a female silhouette. Often the manufacturer's mark is also applied nearby.

How to check the actual purity of a gold item?

Many people are interested in how to test gold jewelry for purity. But how clean will the jewelry really be? And how can you find out the actual gold content of a piece of jewelry?

Let's take a look at what works in gold purity testing and what doesn't.

What is pure gold?

It is generally accepted that gold that does not mix with other metals is pure. 24 karat purity is the highest purity possible and corresponds to approximately 99.9% gold content. Pure gold is very soft and malleable, and has an intense yellow color.

Due to its softness, it is rarely used for jewelry. 24k gold items bend very easily, so pure gold is not a good choice for items that will be worn as jewelry.

How to convert to the metric system and sample correspondence table

In Russia, the metric system is used, which clearly demonstrates the amount of pure metal in grams per kilogram of alloy. The karat system means that 100% pure gold has 24 carats. Banking bars are made from pure 999 purity material, and products made from it are very soft and easily damaged. An ingot with minor scratches immediately loses part of its value.

Expert opinion

Vsevolod Kozlovsky

6 years in jewelry making. Knows everything about samples and can identify a fake in 12 seconds

To convert carats to the metric system, you need to multiply the carat marking by 1000 and divide by 24. For example, 18K x 1000 / 24 = 750. It turns out that 18 carats corresponds to the 750th standard.

Using the following sample correspondence table, you can easily convert all existing gold samples from carats to the metric system:

What purity should the gold in your jewelry be?

Simply put, gold purity is a measure of how much actual gold metal a piece of jewelry contains. The higher the karat of your gold jewelry, the easier it is to scratch.

If a piece of jewelry is described as pure gold, this means that it is made from a gold alloy and is not simply plated with gold.

“Gold plated” and “gold plated” are terms used to describe gold plated jewelry.

Products made from overlaid gold have a thicker layer of gold compared to gold plated ones. Choose false gold or gold-plated jewelry only for occasional wear, otherwise, if the item is worn frequently, its gold layer will quickly wear off.

If you want your jewelry to last longer, you need to buy pure gold.

About this sample

14K gold contains 58.5% gold and 41.5% ligature. It is thanks to additives that it becomes suitable for further processing.

Composition and properties

Depending on the metals in the alloy, gold changes not only its color, but also its properties. Copper and silver are used as alloys, in different proportions, as well as nickel, zinc, palladium, platinum, and very rarely iridium and ruthenium. Ligature metals affect the properties of gold as follows:

1. Red products are durable and do not corrode. This is the most popular color.
2. Silver adds ductility, makes the alloy more malleable for forging, and changes color. The more silver in the composition, the easier the processing.
3. The white color is obtained due to the presence of zinc, which reduces the melting point of the metal.
4. Nickel imparts magnetic properties, the alloy becomes harder and more ductile.
5. Copper adds strength but reduces corrosion resistance.
6. The alloy with platinum in the composition becomes more elastic, the melting point decreases.
7. White gold has the lowest density, which means its mass differs to a lesser extent.

Strength

The softness of gold is the main reason it is used in alloys. The higher the carat value, the less weight and strength the alloy has. 14-karat products contain hard metals, which positively affect its strength, and therefore durability.

Alloy shade chart

The classic option is reddish gold, which contains 8.2% silver and 33.3% copper. This material does not bend, various products are well made from it, it was from this metal that the famous chervonets were cast.

Currently, white alloys are popular. They are used to frame diamonds and are not subject to contamination.

Brand

The manufacturer does not have the right to apply a mark on his own - this is the prerogative of the Assay Office. On domestically produced 14-karat gold, the hallmark contains 4 elements:

• a letter indicating the department that carried out the inspection (“M” - Moscow, “N” - Nizhny Novgorod, etc.);
• female profile in kokoshnik;
• directly sample 585;
• rectangular frame.

In the West, the marking looks different, and it is applied to both gold and gold-plated jewelry. The stamp contains only the characters “14k”.

Care Tips

In order for gold jewelry to please the eye for as long as possible, you need to take care of it. You should not bathe in jewelry, wash dishes, sleep, or apply cream or cosmetics. It is better to store each accessory in separate packaging to minimize friction. Experts advise:

• Wash your jewelry regularly with warm water and detergent dissolved in it;
• do not use abrasives;
• use professional cleaning services.

These simple rules will help keep your jewelry in its original form for a long time.

Reasons for the popularity of 14k products

Products made from 14-karat gold are the most popular, since the ratio of metals in the alloy makes it possible to obtain high-quality and durable jewelry at an affordable price. Finished products retain their attractive appearance for many years, do not fade, and can have different shades depending on the ligature.

In addition, many believe that buying jewelry is a profitable investment, since the price of gold does not fall, but constantly tends to rise. In reality, everything is much more complicated and buying jewelry for investment purposes is a stupid idea.

How to avoid becoming a victim of a scammer

When purchasing gold products abroad, it is important to look specifically at the carat marking. If you come across jewelry with karat markings for sale in Russia, then it most likely entered the country and is sold illegally. When buying such jewelry, you need to be prepared for the fact that imported gold may not reach 585 fineness.

Officially imported precious metals must undergo examination by the Assay Office, after which a standard hallmark is placed next to the original mark, protecting the buyer from deception.

To avoid becoming a victim of fraudsters, you need to carefully check the presence of a stamp and sample. It is better to choose products from trustworthy manufacturers.

How to distinguish gold from gilding

Now let's figure out how to find out whether the gold in front of them is real or not. The easiest way is to check the markings; they are usually applied:

• on the inside of the ring;
• in chains - on rings connecting the clasp to the main part;
• on earrings - on a pin that fits directly into the hole in the ear.

Previously, all stamps were applied by hand, and it was impossible to fake them. Currently, samples are applied using special equipment, and fraudsters have learned to falsify them.

The following facts should alert you:

• the recess of the stamp is clogged with dirt;
• it is impossible to read the sample number or carat marking even through a magnifying glass;
• numbers are unclear or crooked.

There is a lot of advice on the Internet about testing the authenticity of gold by applying nitric acid or aqua regia. But, firstly, it is not easy to find these reagents, and secondly, you risk ruining the decoration. Therefore, it is better to contact an experienced jeweler with this question.

There are also funny and useless ways to check, such as biting the product and checking with a magnet. These methods are unreliable and can be used by scammers.

Expert opinion

Vsevolod Kozlovsky

6 years in jewelry making. Knows everything about samples and can identify a fake in 12 seconds

A product made of real gold should be smooth, durable, and not leave dents or scratches. Gold-plated silver jewelry has a standard of 800, 830, 875, 925, 960.

Over time, the gilding wears off or darkens.

Imported gold plated jewelry is marked with the abbreviation “KGP”. Gilding in English - Gold Platted (a thin layer that will quickly be erased) or Gold Filled (a thicker layer). It is important that the marking contains only the symbols “14k” and no other designations either before or after them.

What is the difference between 9 and 18 carat gold?

As we've seen before, 9K and 18K differ significantly in purity.

Other important differences that depend on purity are the price, durability and color of 9K and 18K products.

Status of Gold: 9 karat gold is not always considered as such!

An important fact to take into account is that 18K alloy is always considered gold, while the status of 9K depends on the country where it is sold.

For example, in the United States, 9-karat jewelry cannot be sold as gold. In the USA, an alloy with a purity of at least 10 carats is considered gold.

Price.

The difference between 9 and 18 carats affects the price of the product. Since 9-karat jewelry contains less gold, it is valued much less per gram.

18k gold jewelry is significantly more expensive because it contains twice the percentage of pure precious metal.

Durability and hardness.

Gold is alloyed with other metals because it itself is very soft. Lower karat alloys will be harder than high karat alloys due to the different amounts of precious metal in their composition.

As a low purity gold alloy, 9K is harder than 18K. This means that 18K jewelry will be easier to scratch or warp.

9 carat jewelry is more durable due to its hardness.

Color.

Alloys with a high content of gold metal will have a richer yellow color than alloys with low purity.

Compared to 9 carat jewelry, 18 carat jewelry looks more rich. So, if you are looking for a ring or bracelet that looks more like solid gold, it is better to choose 18K jewelry.

Jewelry with 9K clarity should be chosen if price is more important to you than color.