Marking of precious metals. Jewelry tests and hallmarks
Sample of precious metals - determination by various analytical methods of the proportion, weight content of the main noble metal (gold, silver, platinum and the other five metals of the platinum group - ruthenium, rhodium, palladium, osmium, iridium) in the alloy being tested; used for subsequent branding, which normatively fixes the data obtained as a result of analyzes - the proportion of precious metal in the manufacture of jewelry, coins, etc.; the brand itself and the content of the main noble metal determined during probing are also called a sample. All commercially available alloys containing more than 30% by weight of precious metal must be assayed and appropriately branded. To date, for all noble metals, a discrete range of their possible contents in alloys (samples) has been established.
Traditional sampling system in Western Europe (in the world):
The basis of the sampling system in Europe is the number of carats of base precious metal in 24 carats of the alloy being tested.
For precious metals, the following samples are most common:
9 carats- the mass of the noble metal is 0.375 of the weight of the alloy
12 carats- the mass of the noble metal is 0.500 of the weight of the alloy
14 carats- the mass of the noble metal is 0.585 of the weight of the alloy
18 carats- the mass of the noble metal is 0.750 of the weight of the alloy
21 carats- the mass of the noble metal is 0.875 of the weight of the alloy
22 carats- the mass of the noble metal is 0.916 of the weight of the alloy
23 carats- the mass of the noble metal is 0.958 of the weight of the alloy
24 carats- the mass of the noble metal is over 0.999 of the weight of the alloy, that is, the metal in its pure form
In addition to the assay marks of the assay chambers that carried out the assaying, precious metal alloys are stamped showing the carat content of the base noble metal in the alloy. There are two types of marks to be distinguished:
Brands like "14K", "18K" mean that the product is made of alloys of the 585th and 750th samples, respectively.
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Note: Items that are silver plated protected with rhodium may not have any hallmarks.
To convert a carat (Western European) sample to a metric value, the value of a carat sample should be divided by 24 and multiplied by 1000.
The dignity of the alloy from which gold, silver, platinum and palladium products are made is determined by a breakdown showing the content of the precious metal in 1000 parts (by weight) of the alloy. Assay supervision is carried out by Assay Supervision Inspections of the Precious Metals Department of the Ministry of Finance of Russia.
Fig.1. Hallmarks basic (а-е) and additional (g, h) for hallmarking.
a - products in combination with one of the additional brands;
b - gold and platinum items;
in - silver products;
g - palladium products;
e - products with seals suspended from them;
e - books with gold leaf and silver;
g - detachable and easily detachable secondary and additional parts of products;
h - products that do not correspond to the declared sample, and those whose sample after
restoration was below the established.
In 1927, the following samples of alloys based on precious metals were established in the USSR:
samples for products made of alloys based on gold - 375, 500, 583, 750, 958;
samples for products made of silver-based alloys -750, 800, 875, 916, 925; 960;
samples for products made of platinum alloys - 950;
samples for products made of palladium alloys - 500, 850.
In Western countries, the carat system is used, in which 1000 metric samples correspond to 24 carats. To convert a sample from metric to carat, the following ratio is used:
where b - sample in carats; x -metric test.
For example, the 750th sample corresponds to 18 carats, the 583rd sample corresponds to 14 carats, the 375th sample corresponds to 9 carats.
Hallmarking of articles made of precious metals carried out by the main and additional stamps (Fig. 1).
The main hallmarks include the hallmarks of the letters "A", "B". "B" and "G"
Stamp letter "A" has a round shape and consists of an identity badge (emblem
hammer and sickle against the background of a five-pointed star with a three-digit sample number) and a cipher
assay inspections.
Stamp letter "B" may be of several types:
a stamp in the form of a spatula, consisting of a certificate mark, a cipher of the inspection of assay supervision and a sample, is intended for hallmarking gold and platinum products;
a stamp in the form of a rectangle with convex opposite sides, consisting of a certificate mark, an inspection code and a sample (750, 800, 875, 916, 925 and 960), is used for hallmarking silver products;
truncated-oval stamp, consisting of a certificate mark, inspection code and sample (500, 850), Designed for hallmarking products made of alloys based on palladium.
Stamp of the letter "B"- bilateral, round; consists of two parts: a badge of the certificate with the code of the assay inspection and a round badge with the numbers of samples. They brand products made of precious metals on plates attached to them.
Stamp of the letter "G" has an oblong shape with rounded corners. It consists of a certificate mark, an inspection code and a sample and is intended for hallmarking thin-sheet (leaf) gold and silver.
Additional hallmarks include the hallmarks of the letters "D" and "E".
Stamp of the letter "D" has a square shape with cut corners. This brand is used for branding detachable, secondary and additional parts of products made of precious metals.
Stamp of the letter "E" has a square shape with cut corners and the letters "NP".
Designed for hallmarking precious metal products that do not correspond to the declared sample.
Hallmarking of products made of precious metals is carried out based on the results of testing them on the touchstone and control analysis with the following deviations from the established samples:
for gold-based alloys no more than +/- 3 tests;
for silver-based alloys no more than +/- 5 tests;
for alloys based on platinum no more than +/- 5 samples;
for alloys based on palladium no more than +/- 5 samples.
In practice, the simplest method for determining a sample of precious metals and their alloys is used - by applying a solution of gold chloride directly to the product under test. A drop of gold chloride solution is placed on a clean surface of the tested metal or alloy and the result is monitored.
As a rule, a deposit stain appears on the wetted surface, the color of which determines the metals.
Determination of metal by applying a solution of gold chloride:
Color of the investigated metal: White.
Spot color: Dark green - Yellow with gas release, gradually turning black - Black.
Spot formation time, s: 1-2 - 1-2 - 30-40.
Metal to be determined: Pure silver or a high-grade silver-based alloy. - Aluminum - Tin.
Spot formation time, s: 30-40.
Defined metal: Platinum.
Color of the investigated metal: Greyish-white.
Spot color: Yellow, quickly blackens.
Defined metal: Zinc.
Color of the investigated metal: Bluish-gray.
Spot color: Dirty yellow.
Spot formation time, s: 1-2.
Defined metal: Lead.
Spot color: The solution has no effect.
Spot formation time, s: 1-2.
Defined metal: Gold and its high-grade alloys with silver.
Color of the investigated metal: Yellow.
Spot Color: Chestnut.
Defined metal: Low-grade (less than 583 samples) alloys of gold with silver and copper.
Color of the investigated metal: Yellow.
Spot Color: Black.
Spot formation time, s: 1-2.
Defined metal: Brass.
Color of the investigated metal: Whitish-yellow.
Spot Color: Black.
Spot formation time, s: 1-2.
Metal Detected: A base alloy of silver and copper.
Spot color: The solution has no effect.
Spot formation time, s: 1-2.
Defined metal: High-grade alloy (above 583 samples) of gold with copper.
Color of the investigated metal: Red.
Spot color: Golden or chestnut.
Spot formation time, s: 60-360.
Defined metal: Low-grade alloy of gold and copper (below 583 samples).
Color of the investigated metal: Red.
Spot Color: Black.
Spot formation time, s: 1-2.
Defined metal: Copper.
Sample system in Russia:
Due to historical features, branding in Russia appeared later than in other countries. The first Moscow brand - a double-headed eagle, accompanied by a date expressed in Slavic letters, refers to 1651-1652. The first hallmarks were not yet an indicator of the sample in the exact sense of the word. The brand only indicated that the silver was no worse than the sample recognized by law, but the sample itself did not have a precisely defined sample. As a rule, high-quality gold was from the 83rd to the 85th test and higher, which corresponded to the sample of "Lyubsky thalers" or "efimki" - imported coins that were melted down to make things. In the last quarter of the 17th century, the law allowed a more low-grade sample - “levok”.
A stigma appeared - in the oval the word "levok".
In Russia, the state branding of products made of precious metals is legalized: silver - in 1613, gold - in 1700.
in the USSR: platinum - in 1927, palladium - in 1956.
The system of trials and hallmarks in pre-revolutionary Russia:
For all cities in the XVIII-XIX centuries, the hallmarks consisted of:
from a stamp with the coat of arms of the city with or without a year in shields of various shapes;
from a stamp with the initial letters of the name and surname - the assay master's "name book";
from the brand of the master who made the thing, without indicating the year;
from a stamp with two numbers indicating the sample, that is, the number of spools
pure silver or gold in a ligature pound.
Masters, workshops, firms and factories were required to put their brand names before the presentation of products to the state assayer.
Until 1927, Russia had a spool designation system based on the Russian pound, containing 96 spools. Similarly, a system was established when one spool was equal to 1/96th of the gold in the alloy.
36 spools - the mass of the noble metal is 0.375 of the weight of the alloy
48 spools - the mass of the noble metal is 0.500 of the weight of the alloy
56 spools - the mass of the noble metal is 0.585 of the weight of the alloy
72 spools - the mass of the noble metal is 0.750 of the weight of the alloy
84 spools - the mass of the noble metal is 0.875 of the weight of the alloy
88 spools - the mass of the noble metal is 0.916 of the weight of the alloy
92 spools - the mass of the noble metal is 0.958 of the weight of the alloy
96 spools - the mass of the noble metal is over 0.999 of the weight of the alloy, that is, pure metal
To convert a spool sample to a carat (Western European) value, the spool sample value should be divided by 4. To convert a spool sample to a metric value, the spool sample value should be divided by 96 and multiplied by 1000.
The system of samples and hallmarks in the USSR:
In 1927, as part of the transition to the metric system of measures, by recalculating shares in spools, a new system was created in which the sample was designated by the number of thousandths of the weight of gold in the alloy. It is still in use today and is described below.
At the same time, a new branding system for tested metal was installed. 3, sometimes 2 hallmarks were applied: the manufacturer's mark, the numerical designation of the sample and the assay mark in the form of a five-pointed star in a frame. In the absence of a numerical designation, the shape of the stamp frame determined the parameters (including the sample) of the tested alloy.
The system of samples and hallmarks in modern Russia:
Currently, hallmarks with the image of a woman's head in a kokoshnik are used for hallmarking jewelry. Testing and hallmarking of jewelry and other household items made of precious metals in Russia are carried out by the Russian State Assay Chamber under the Ministry of Finance of the Russian Federation, established in accordance with Decree of the Government of the Russian Federation dated February 2, 1998 No. 106 “On the Russian State Assay Chamber.” The basis of the sampling system in Russia is the number of milligrams of the base noble metal in 1 gram (or gram per kilogram) of the alloy being tested. In the Metric System of Measures and Weights, the value of a sample can also be considered as the number of weight parts (shares) of the base noble metal per 1000 weight parts (shares) of the alloy being tested.
For precious metals in Russia, the following samples are established:
gold (more details about the purity of gold) - 375, 500, 583, 585, 750, 958, 996, 999
silver - 750, 800, 875, 916, 925, 960, 999
platinum - 950
palladium - 500, 850
The numerical values of the shares were mainly established by recalculating the shares of the carat system (see above).
Sample determination methods:
Touchstone
Chemical analysis using gold chloride, aqua regia, etc.
Spectral analysis
Alloy composition and application:
The most common alloy is 583 gold; alloys of this sample can be of different colors depending on the quantitative ratio of the non-ferrous metals contained in them. For example, if an alloy of 583-carat gold (58.3% gold) contains approximately 36% silver and 5.7% copper, the alloy acquires a green tint; at 18.3% silver and 23.4% copper - pink; at 8.3% silver and 33.4% copper - reddish. Depending on the ligature, it can have different melting points and hardness, these alloys have good solderability. 958 gold alloys are fragile and therefore are used in limited quantities. Alloy 958 is three-component, in addition to gold, it contains silver and copper, it is used mainly for the manufacture of wedding rings.
The alloy has a pleasant bright yellow color, close to the color of pure gold. Very soft, as a result of which polishing on the product does not last long. An alloy of the 750th sample is three-component, it contains copper and silver, in some cases rhodium, palladium, nickel and zinc can be used in the form of a ligature. Color from yellowish green through reddish hues to white. The alloy lends itself well to soldering and casting, is a suitable base for applying enamels, however, when the alloy contains more than 16% copper, the color of the enamel becomes dull. It is recommended to use in the manufacture of products with a thin embossed gouge, filigree and settings for fragile gems, intense diamonds. An alloy of 375-carat gold usually contains: gold 37.5%, silver 10.0%, copper 48.7%, palladium 3, eight %.
Used to make wedding rings.
For the manufacture of jewelry with diamonds, “white gold” is widely used, which contains:
in an alloy of gold of the 583rd test - silver 23.7-28.7%, palladium 13.0-18% or
nickel 17%, zinc 8.7%, copper 16%;
in an alloy of gold of the 750th test - silver 7.0-15.0%, palladium up to 14%, nickel up to
4%, zinc up to 2.4%, or nickel 7.5-16.5%, zinc 2.0-5.0%, copper up to 15%.
The most common alloy is 875 silver. It is used to make jewelry and table setting items. 916 alloy is used for the production of table setting items with enamel coating; alloy of the 960th test - for the manufacture of filigree products.
Alloys of platinum and palladium are used in jewelry in small quantities.
Silver and brass products are electrolytically coated with a thin layer of 999 gold (gold plating) or 999 silver (silver plating) to protect against rapidly occurring oxidation and to improve their decorative properties. Platinum alloy is rare in modern jewelry, it has lost its positions for white gold. For some jewelry, a two-component 950 alloy is used, which, in addition to platinum, includes copper and iridium. The addition of iridium significantly increases the hardness of the alloy.
Palladium is not yet generally recognized as a stand-alone jewelry metal, but it has good prospects because it is cheaper than platinum, has a more intense white color, better machinability, and air tarnish resistance similar to platinum.
Interesting:
Hallmarking of household jewelry has been known since the Middle Ages (for example, in England and Italy since the 15th century, in France since the 16th century). In a number of countries branding was introduced in the 20th century (for example, in Canada since 1913, Australia since 1923). In some countries, household jewelry made of precious metals, although branded (more often by the manufacturers of products), control over the Sample by the state is not mandatory or weak (for example, Australia, Belgium, Denmark, Italy, Canada, Malta, USA, Germany, Switzerland, Sweden).
Stamp on gold :
When buying a gold item, you need to pay attention to the stamp on the gold. As a rule, on a chain or earrings, a gold stamp is placed next to the lock, and on rings, on the “wrong side” of the product;
Hallmarking of gold with the image of a sample can only be carried out by specialists of the Chamber of Assay Supervision, and not by craftsmen who make jewelry. Many craftsmen put their own brand, the so-called "name book", which will say little to an uninformed buyer. Recently, the “name book” indicates the year, city and personal code of the master who made the piece of jewelry;
Some jewelry workshops work "in the dark", making high-quality gold items, but without branding them. In this case, it is worth contacting specialists who will help you determine the gold standard. It is best to purchase gold jewelry in large stores, where you can see the brand on gold under a magnifying glass, and you also need to keep all receipts and certificates for a refund in case the gold jewelry does not match the declared standard.
Beauty will save the world! This phrase is great for discussing jewelry made from precious metals and stones. Using these expensive components, a real jeweler is able to create an alloy in any proportion. But after making jewelry from such an alloy, it is difficult to evaluate it and compare it with other similar jewelry. For these purposes, in the 17th century, jewelers began to apply special criteria for jewelry, such as gold samples, which make it possible to identify products by the content of the precious metal, the presence of additions of other elements, and color.
What are gold samples
The ratio of the base metals in the alloy determines its quality index. These metals include gold (aurum), silver (argentum), copper (cuprum). The legislation of the Russian Federation establishes the mandatory branding of any alloys based on precious metals. An imprint is made on the jewelry, indicating the quality of the alloy. This impression is called a hallmark or stamp. Historically, hallmarks around the world have followed the weight standards used. The metric system indicates the content in parts of gold with a purity of 99.99% in 1000 parts of the alloy.
Carat sampling system
Absolutely pure gold is recognized with a content of 99.99% in the alloy. In the carat system, this indicator is designated 24k. Further, in descending order, the standard 23k, 22k, 18k, 14k, 12k, 9k, 8k carat values are used. What does the test on gold products in carats mean? An 18 carat decoration means that there are 18 parts of pure yellow metal in 24 parts of the alloy. This system is used in the USA, Canada, Asian countries and some European countries.
Sample spool system
Originally Russian is the spool system, introduced in 1798 during the reign of the Russian Emperor Pavel Petrovich. Its basis was the weight standard used at that time - the Russian pound, which consisted of 96 spools. When the brand was set in 96 spools, the gold content in the tested alloy was 99.99%. Further, this figure decreased to 36 spools. To convert from a spool system to a carat one, it is necessary to divide the hallmark indicator by 4.
Hallmarks of Russia and foreign countries
From the middle of the 17th century in Russia, the use of a double-headed eagle began to be used to hallmark gold and silver items. The content of pure gold during this period was 83–85%, which corresponded to the purity of imported gold coins of thalers or efimki, from which jewelry was made. The hallmarking of gold objects in Russia was legalized by a royal decree under Peter the Great in 1700. In Russia, the 56th sample is most widely used, which corresponds to the modern 585.
During this period, coats of arms of cities and the number of spools in a ligature pound were used for hallmarking. Since 1899, a female face in a kokoshnik has been used for branding, which in 1927 was replaced by the profile of a worker with a hammer, and since 1957, a hammer and sickle against the background of a five-pointed star. In Asian countries, hieroglyphs were used for branding. In Europe - coats of arms of countries and cities with an indication of the sample in carats. The type of brand designation should not differ much for different manufacturers.
What are the samples of gold
In life, we come across jewelry from this “despicable” metal (earrings, chains, rings) of different colors. Additional inclusions in a precious alloy of other metals is called a ligature. Objects, depending on the content of the ligature in the alloy, become green, red, orange, yellow, platinum and white. The main contents of the ligature are silver, copper, platinum (palladium), zinc. In non-precious white alloys, nickel is used instead of platinum. It is important for the buyer to know what sample gold is before going to a jewelry store.
999 proof
The highest content is 999 quality index. This alloy contains 0.01% impurities. It is practically pure gold. For the manufacture of jewelry, this alloy is not used, since it is subject to deformation and has a dull yellow color. This alloy is used to create bank bars of various weights for sale to investors who want to save money or earn on the growth in the cost of precious metals.
At all times, noble metal has always been in price. During periods of financial crises, the demand for it and other precious metals rises sharply. Their quotes on all world exchanges are the main economic indicators. Bank bullion is sold by all banks in the world and is included in the deposit portfolios of large and small investors, and jewelry has always given women the opportunity to look rich and beautiful.
925 test
Hallmarking is subject not only to objects made of gold, but also of silver. If the product is 925, it means that you have a high quality silver jewelry. The amount of pure silver in it is 92.5%. As a ligature, along with silver, germanium and cadmium are used to maintain the original brilliance and the absence of darkening of jewelry over time. These additives were used by the old craftsmen, they give the silver masterpieces a magnificent look.
875 sample
The mark on the 875 jewelry indicates the maximum percentage of silver in the amount of 87.5%. Items made from this metal are popular. They always tried to fake it. Possible replacements for silver include alloys of lead, aluminium, zinc. To give a silver sheen, fakes are coated with pure silver. When buying precious metal jewelry, pay attention to the hallmark number on all parts of the pendant, chain or ring. In the store, jewelry should be sold only if they have a seal with an attached passport of the manufacturer.
750 sample
For ease of understanding what a test on gold means, you should mentally break the product into 1000 parts or fractions. The numbers 750 mean that this product contains 750 parts of pure precious metal. This is the highest standard of gold in jewelry used in industry. 75% gold combined with copper gives objects made of this alloy a characteristic reddish tint. 18 carat alloy is widely used for jewelry making in Asian countries, it is used to create gold plating for men's and women's accessories.
585 sample
The most common gold samples on an industrial scale are 585. The pure gold content in this alloy is 58.5%. The ligature in it is divided in the ratio of silver to copper, as 1 to 4.3. This is the empirically established ratio of the volume of gold and additives. Jewelry labeled 585 has a beautiful color and shine. Pendants, chains, rings, earrings, brooches and bracelets are made from this alloy in our country. To reduce the likelihood of counterfeiting, objects made of this alloy are stamped 5S5 by the electrospark or laser method. It is more difficult to fake than a simple print.
583 sample
In the first years of Soviet Power after 1927, the stigma 583 was used. This is the gold standard of the Soviet Union. Most of the rings and earrings we inherited from our parents are of this quality. In the post-war period, 14 carat gold was widely used in Europe. If 14 is divided by 24 and multiplied by 1000, you get 583. A large number of wedding rings, jewelry with diamonds, rubies, sapphires and semi-precious stones are made from this alloy. In 2000, the stigma 585 became the standard of Russia.
500 test
If the content of yellow metal and ligature is equal, the sample becomes equal to 500. For industrial purposes, this standard is not used, but in the production of private craftsmen this high-quality composition of the alloy is used. Jewelry made from it with an original design or with a special theme get the opportunity to be fully appreciated. Abroad, brooches, cufflinks, and cigarette cases are made from 500-grade alloy.
385 test
Gold jewelry with a quality value of 385 contains more than half of its amount of additional materials. With an increased copper content, the jewelry gets a reddish tint. Silver in the alloy gives the products a whitish or even light white color. In order to make jewelry, alloys with good malleability and low melting point are used. This temperature for aurum is 1080 degrees Celsius, for silver - 1550, for platinum - 1780. To reduce the melting point, zinc is used in the alloy.
375 test
The cheapest alloy for making gold jewelry is 375 quality alloy. The large amount of copper and silver in it leads to rapid oxidation and the appearance of dark spots. In the presence of small details, it is difficult to restore the original appearance. Such an alloy is inexpensive, and provides an opportunity to produce mass cheap jewelry. As long as jewelry production exists, so many organizations have been involved in standardization, accounting and control over the circulation of precious metals. In the Russian Federation, this is done by the Assay Chamber of Russia.
Gold samples in the USSR
In the USSR, for the manufacture of jewelry and ceremonial products and semi-finished products from precious metals, GOST 30649-99 was used, which establishes the following types of gold samples:
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Which sample of gold is betterComparing the price and appearance of jewelry, the 585 assay has become widespread in European countries. Jewelry made from it retains its original appearance for a long time. The cost of such goods is lower than the products from 22 and 24 carat aurum of Arab sheikhs. The melting point, taking into account the use of zinc, is low. The brand on gold items breaks through on areas invisible during use - inside the rings, on the clasps of chains and earrings. In our time, the most exquisite and elite are the jewelry of Italian masters. The most expensive sample of goldThe highest quality indicator in jewelry in the metric system is pure gold with a purity of 99.99%. Chemically pure, 24 carat gold is widely used in Arab countries. In the jewelry markets of Dubai, you can see jewelry of huge size and bright yellow color. There is a historical explanation for this. The history of industry in these countries is more modest than in Europe. 50 years ago, in their place was a desert, with Bedouins wandering through it. Jewelry was made by hand, and their size had to confirm the wealth of their owners. Video
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Throughout history, gold has been prized for its natural beauty and brilliance. For this reason, in many cultures, gold was identified with the sun.
By itself, a metal such as gold in its pure form is not used, because it is very soft and easily susceptible to mechanical damage. In order to preserve its original noble appearance, which everyone is used to contemplating in jewelry, it is customary to add various, more stable metals or alloys that give gold strength. It is customary to call such alloys a ligature, and in most cases silver or copper acts as it, in rare cases zinc, platinum, nickel and palladium are added. Depending on the amount of other metals, gold becomes less prone to scratching and warping.
What is the difference between carat and metric systems?
Around the world, several systems are used to recognize the amount of ligature included in a gold alloy. The most famous are the metric and carat systems. Due to the fact that gold was used long before globalization, different continents formed their own systems for calculating gold. For example, the weight of gold is measured in troy ounces and simultaneously in grams (1 troy ounce = 31.1034768 grams), while its purity is measured in carats and thousandths.
One carat is 1/24 of the pure precious metal in the alloy.
The minimum number of carats of gold varies by country. For example, in the US, 10 karat is the minimum gold standard, and gold with a purity of 14 karat is the most popular. In France, Austria, Portugal, Ireland and the UK, you can call anything that has 9 carats. And in Denmark, Greece and Germany, the minimum number of carats is 8. 
The carat system is also used to measure the weight of a gemstone, but the two systems should not be confused. One carat of gold corresponds to 41.6 grams, while 1 carat of a precious stone is equal to 200 mg. 24 carat gold is equivalent to 999.9 fineness in the metric system and is considered pure. Strictly speaking, 24 carat gold should be equivalent to 1000 fineness. However, in practice it is impossible to achieve 100% purity of gold, and any pure gold will have some impurities, so it was agreed to accept 24 carat gold for 999.9 fineness. In the carat system, there are indicators 9, 10, 12, 14, 18, 23, 24.
In Russia, the metric system has been used for many years. It is simpler and more understandable and indicates the number of grams of gold that is part of an alloy weighing 1 kg. So, if in 1000 grams of the alloy there is 585 grams of noble metal, and the ligature, respectively, weighs 415 grams, then the products that will be made from this ingot will wear a sample of 585.
A sample is the amount of precious metal in an alloy, expressed in thousandths. The amount of ligature is the reciprocal of the sample.
Until 1927, first in the Russian Empire, and then in the Soviet Union, a different sampling system was used, which was called the spool system. For her, 92.72 and 56 samples were characteristic. 1 spool equals 96 parts. Until now, sometimes there are jewelry with such markings. Since 1928, it was decided to switch to the metric system, indicating the amount of gold per 1000 grams of alloy.
Correspondence between different sample systems
In the decree of June 18, 1999, under No. 643 “on the procedure for testing and branding products made of precious metals”, the following samples were established for the metric system: 999, 958, 750, 585, 375.
What is the difference between different gold grades?
Where did such a variety of gold alloys come from? Each sample appeared at a certain point in time and satisfied a certain need of people. Various samples exist for their own task, which determines the required proportion of the precious metal in the alloy, as well as the composition of the ligature in it.
375 sample
In this sample, pure gold does not exceed 37%. The remaining 63 percent is silver and copper. Depending on the metal that will be used as a ligature, the main shade of the product will be either bright yellow or reddish. The gold of this sample tends to quickly oxidize and form iron sulfide on the surface of the jewelry. This gold alloy is the lowest grade in the world. Inexpensive jewelry is made from it, for which there is a massive demand. As a rule, these are wedding rings.
500 test
This sample is little known, it contains no more than 51% of the base metal, and the rest is impurities of silver and copper. The products of this sample have an ugly color, although they are not amenable to rapid oxidation, therefore, such alloys are practically not used anywhere, since they had to be abandoned in favor of samples that have a more pleasant appearance in jewelry.
583 sample
In the composition of such an alloy, a combination of pure gold in the amount of 58.3 percent, copper 33.5 percent and silver 8% is common. One kilogram of a 583-carat ingot contains 583 grams of pure gold. The remaining 417 grams are copper and silver. Until the moment when the alloy of 585 was created, gold with 583 was widely used in the Soviet Union for the manufacture of jewelry. The appearance of this sample occurred at the time of the transition from the carat system to the metric one. 583 sample is equal to 14 carats. After some time, it was abandoned, in favor of the currently popular test - 585.
585 sample
Jewelry 585 is the most common and popular among consumers. Now it has completely absorbed the 583 sample. This hallmark is used in marking the largest share of products that are produced in the world. Jewelry and other products made of this quality alloy are distinguished by their characteristic color, and they also have good strength and stability at an affordable cost that does not exceed the permissible range. As part of sample 585, the main part is occupied by pure gold, more than 60%, everything else is an alloy consisting of an alloy of nickel, palladium, silver and copper (40%). Gold of this sample is not subject to loss of luster and brightness under the influence of the sun and it does not tend to oxidize when exposed to air. It is held in high esteem by jewelers, because it lends itself perfectly to forging.
750 sample
This sample represents 75 percent of the noble metal. The alloy contains 25% silver, palladium and copper. The alloy is characterized by the ability to change color depending on the percentage of any additional metal included as an impurity. For consumers, it is preferable to buy products in lighter shades, where silver predominates. In general, there are products that are red or even dark green. Jewelry made from alloys of this type is very expensive and has a great appearance. Gold 750 perfectly lends itself to polishing and mechanical processing, but at the same time it is easily scratched and bent.
958 test
Gold of such a sample is not used in the manufacture of jewelry, since the percentage of its content in the alloy is almost 97%, and this makes the metal soft and prone to deformation. From an alloy with such a gold content, collectible coins are made, or any items for an individual order, since it has a very high value.
.999 proof
The most expensive alloy in the world is considered to be pure gold, which has a fineness of 999. The metal itself is soft, and therefore, it is inconvenient to use. Many years ago it was used to make wedding rings. Their shape was very thick, the products were distinguished by their great height. This contributed to a longer use of jewelry, they crumbled and did not bend very quickly. Now 999 gold is used for the manufacture of ingots intended for storage. Due to the high plasticity, small ingots are sealed in special transparent cases. In them, soft metal can be stored in perfect condition much longer.
How to determine the purity of gold?
The use of modern methods today allows you to accurately determine how high quality a product is. When buying a piece of jewelry, everyone had to see a special marking, which is used for each existing sample separately. But, no one is immune from buying a fake, even if it has the highest standard. Therefore, so that there is no doubt that the product corresponds to the declared sample, the drop method, an electronic detector, a special touchstone or assay needles are used. There is also a muffle method and a chemical-analytical method.
The drip method consists in applying a special assay chemical reagent to the product, then the color of the sample is compared before and after the reaction. As a rule, chlorine gold is used for such purposes, which acts as an assay reagent for products of various samples, up to and including the six hundredth. On jewelry 585 samples, a light brown stain forms after interaction with the reagent. The green spot will be on 375 gold. The lower the gold standard, the darker the color will remain.
Brass strips, at the ends of which the thinnest lines of precious metal are soldered, are called assay needles. To determine the gold of different samples, there are needles of different colors.
Touchstone is a bar with a smooth, polished surface. A product is carried along it, which forms a line behind it. Its color characterizes the sample. For the manufacture of such bars, siliceous fine-grained shale is used.
A special electronic detector is able to determine in 5 seconds how much pure metal is contained in the alloy, expressing the figures in carats. The sample range is from six to eighteen carats, which in the metric system refers to 375-750 samples. The detector distinguishes a real massive gold item from a simple gold coating with a thin layer. This device is widely used by the jewelry industry, as it determines the content of the noble metal in the alloy with high accuracy. Its operation is based on an electrochemical reaction. These samplers can also be used in pawnshops, workshops and buying shops.
Many buyers who want to buy gold jewelry are trying to become the owners of an expensive piece or trying to find one that has a very high standard. There is no need to do this, because it is not in vain that for many years the 585 test has remained popular and in demand, which has proven itself in the best way, even if jewelry is worn daily without taking it off.
In terms of its strength, products of high standards can be compared with plasticine, which loses its original appearance at the slightest pressure.
You need to buy jewelry only in specialized stores or salons, and after the presence of the appropriate brand has been verified. In these establishments, all items correspond to the proper quality, since no one wants to risk their reputation and created name. In this way, you can avoid purchasing a fake that will not contain gold at all and has no value at all.
In this article:
Almost never in jewelry is gold and silver used in its pure form. These metals have high ductility and softness, as well as low wear resistance, which makes them unsuitable for jewelry and products. Alloys that are used instead of these metals contain a certain percentage of gold and silver. Depending on how much is contained in the noble metal alloy, it has a certain sample. Consider the tables of which will be presented below.
Now in our country they use the metric system. It shows the content of pure metal in the alloy in thousandths. In the West, the carat system is more popular. Pure gold has a hallmark of 24 carats. An alloy containing half gold is 12 carats, and the most common 585th sample is 14 carats.
Test on a gold item
In the Russian Empire there was a different sample system - spool. It is somewhat similar to carat, but in pure gold there were not 24, but 96 spools, the rest of the sample values are also proportional to the percentage of pure metal.
gold samples
Pure gold is not found in nature, it is one that has various additives. After its purification, additional metals are still introduced into the metal - to improve its characteristics. Gold is alloyed with silver, nickel, copper, palladium, platinum, zinc. In the Russian Federation, such samples are legally allowed for use in jewelry - 375, 500, 583, 585, 750 and 958. But, in addition, in the world, as in Russia, other samples can be found for other purposes.
| gold samples | carat system | Spool system |
|---|---|---|
| 990 and above | 24 K | 96 |
| 958 | 23 K | 92 |
| 916; 917 | 22 K | 88 |
| 875 | 21 K | 84 |
| 833 | 20 K | 81 |
| 800 | 19.2 K | 76.8 |
| 792 | 19 K | 76 |
| 750 | 18 K | 72 |
| 625 | 15 K | 60 |
| 585; 583 | 14 K | 56 |
| 500 | 12 K | 48 |
| 417 | 10 K | 40 |
| 375 | 9 K | 36 |
| 333 | 8 K | 32 |
1) Gold 350. This alloy contains 35% pure gold, the alloy may have a yellowish or reddish tint. Due to the low content of gold, it loses almost all of its useful properties - such as, for example, inertness, therefore it oxidizes very easily and becomes unattractive. It is most often used for making cigarette cases, figurines, for finishing furniture, interiors, etc. Jewelers can use this alloy to obtain metal of a higher standard. There are also 325 and 333 samples, however, they are rare and do not make sense in jewelry.
2). Such an alloy was very popular in the USSR, wedding rings were mainly made from it, since it is stronger than the most popular one - the 575th test, and is more comfortable to wear. Such a metal is not called gold, but a gold-bearing alloy.
3) 583 Sample. Almost the same as the 585th sample is not used now, but in the days of the USSR it was very common. Its replacement with 585 was due to the popularity of this type of alloy. The paradox is that it happened that 583 assay contained even more gold than 585.
4) Gold 585. The most popular and running alloy. It is widely used to make jewelry in a wide variety of colors - pink, yellow, green, white, red and others. It goes well with stones, both precious and semi-precious. It is easy to process and has sufficient stability. Can be used for daily use.
5) 750 gold is another common standard. So-called . The alloy is durable, although it is used in products that are not too large. Somewhat inferior to the 585 test in strength. It lends itself very well to processing, for which it is valued among jewelers. May be white or have a greenish, pinkish or reddish tint.
6) Gold 875. Not common with us, but the most common gold in the countries of the Middle East. It is practically impossible to find such a sample on a product, because where it was made, it will be tested by a carat system of samples. In Mexico, coins are minted from such an alloy.
7) 999 gold sample. Such gold is called pure gold. It has no impurities and has the highest cost. It is rarely used for making jewelry, because the metal is very soft.
Basically, this metal is used in banking. It is used to make ingots and coins for investment. Sometimes it can be used to make awards and medals.
Test on a silver ring Silver samples
Silver in jewelry has a higher standard than 925 gold, and 800 is considered the minimum silver standard. There is silver with lower standards, but it is not used anywhere.
| Silver samples | carat system | Spool system |
|---|---|---|
| 999 | 24 K | 96 |
| 970 | 23.28 K | 93 |
| 960 | 23 K | 92 |
| 950 | 22.8K | 91 |
| 940 | 22.56 K | 90 |
| 925 | 22 K | 88 |
| 916 | 22 K | 88 |
| 900 | 21.6 K | 86 |
| 875 | 21 K | 84 |
| 830 | 20 K | 80 |
| 800 | 19 K | 77 |
| 770 | 18.5K | 74 |
| 750 | 18 K | 72 |
| 625 | 15 K | 60 |
| 600 | 14.4K | 58 |
| 500 | 12 K | 48 |
| 375 | 9 K | 36 |
1) 800 silver. This alloy contains 80% silver. The rest is copper, although there are other impurities. Due to the high copper content, the alloy has a yellowish tint. It has casting properties, which makes it possible to make durable devices from it. Over time, it does not wear out and does not change shape.
2) 830 silver sample. Such silver should contain at least 83% pure metal. In appearance, it is no different from 800 silver, has a yellowish tint and is considered low-grade. It is often used to make decorative ornaments.
3) Silver 857. It contains at least 87.5% silver. It can also be found in jewelry, but is most often used for the manufacture of silverware, figurines and dishes. Has a less pronounced tint.
4) 925 sterling silver. The bulk of silver jewelry on the market is made from it. It is also called sterling silver. Its color does not differ from the color of pure metal and is practically in no way inferior to white gold and platinum in its appearance.
Less than all other samples, subject to oxidation. Considered the silver standard. It is also used for minting collectible coins in industry.
5) 960 silver sample. Silver in this alloy is not less than 96%. In physical properties, it is no different from pure silver. Works well, soft, plastic. It is used for the manufacture of highly artistic products, not applicable for wearing.
6) 999 silver sample. As with gold, 999 is the highest. 1000 proof does not exist, it can be used as something virtual or conditional. This is due to the fact that at the moment there is no technology that would make it possible to obtain silver of such purity.
In the manufacture of jewelry is not used. It is mainly used in cans for the manufacture of ingots and coins. Also silver 999 covers cutlery, jewelry and radio elements. It is also used in medicine, for example, they cover milk teeth to prevent further development of caries.
It is almost impossible to determine the metal sample by eye. All jewelry made in the country must have an approved sample and be approved in everyday life. If the product is brought from abroad, it must bear the stamp of the assay supervision of the Russian Federation. When choosing gold jewelry, it is best to buy 575 or 750 as they are resistant to impact. Silver products choose 925 samples.
To determine the quality of such a precious metal as gold, a system of samples was invented, showing the amount of pure metal in the product.
The need for this system came along with the advent of gold jewelry and products for sale. Due to the fact that pure gold is very soft and brittle, various impurities (copper, zinc, silver, palladium) are added to it. In general, several basic sampling systems are used. In Russia and neighboring countries, the metric system of samples is used, in the European Union and Western countries, preference is given to the carat system. Until 1927, the Soviet Union used a spool-type sampling system.
Classification of gold samples
In general, two main systems of samples are distinguished, these are metric and carat, but very often on old antiques you can also find a spool sample. 
Spool system
The spool sampling system was created in Russia in 1711, and was in use for more than two hundred years, until 1927. This system, like others, indicated the exact number of precious metal in the alloy, for gold the maximum indicator was 96. In general, the following gold samples were established: 56, 72, 82, 92, 94.
To convert spool to metric, you can use the following formula:
X / 96 * 1000 \u003d Y, where X is the spool test, and Y is the metric72/96 * 1000 = 750 It turns out that 72 samples in spools = 750 samples of gold
Metric system
The metric probing system replaced the spool system in 1927, and has been operating in the Russian Federation and neighboring countries to this day. There are the following metric samples for gold used in Russia: 375, 500, 583, 585, 750, 958, 999. It is measured very simply - let's say you have a gold jewelry with a total weight of 1,000 grams of 585 samples, which means that pure it contains 585 grams of gold, the rest is ligature additives (copper, zinc, etc.).
Carat sampling system
The carat sampling system is used mainly in the USA, Canada and some countries of Western Europe. Therefore, questions are often asked: 18 carats of gold, what is the hallmark? Or 14 carat gold, what's the hallmark?
So, the basis of the carat system is the number of carats of precious metal in a 24-carat alloy.
That is, in simple words: if you have 18 carat gold, and you want to know how much it is in the metric system, then you need 18/24 * 1000 = 750. This means that 18 carat gold corresponds to 750 samples.
Marking and branding of gold jewelry
In Russia, on all jewelry according to GOST, next to the numbers that 
designate a sample, a brand is put. The brand has the form of a female head in a kokoshnik, which looks to the right. In the USSR, the stigma looked like a star with a sickle and hammer inside.