How to recognize gold jewelry?
- Wear it all the time
- Check the punch
- Use a magnet
- Look for signs of wear
- Rub on ceramic
- Bite test
- Weight test
- Density test
- Using an electronic gold tester
- X-ray fluorescence spectrometry (XRF)
Does a piece of jewelry always have a hallmark?
No hallmark on handcrafted or antique jewelry
What should I do if a piece of gold jewelry doesn't have a hallmark?
Gold jewelry has fascinated mankind for millennia, symbolizing wealth, power and prestige. However, in a market where counterfeits abound, knowing how to recognize
whether buying, selling or simply estimating the value of a piece of jewelry. Real gold has unique characteristics that differentiate it from other metals and imitations. This article explores in depth how to recognize a piece of gold jewelry, whether you're an expert or a curious amateur.
To be sure of owning a piece of gold jewelry, put it to the test! Wear it day and night, in the shower and especially on hot days.
Real gold won't discolor or leave any marks on your skin. If, on the contrary, another color appears beneath the golden surface, or if your skin shows a greenish mark
Pure gold or 18-carat gold jewelry does not react in this way.
If you have a gold ring and after a few days, the color starts to deteriorate and your finger shows a greenish tinge,
this indicates that the ring is not solid gold, but simply plated.
Genuine gold jewelry usually bears a hallmark indicating its gold content, such as "18K", "750" or "24K".
In Europe, these marks are mandatory for jewelry weighing more than 3 grams.
Look for hallmarks in inconspicuous places, such as the clasp or the inside of the ring. The main hallmarks include :
- Tête d'Aigle: Indicates that the jewel is made of 18-carat gold.
- Seahorse: Means that the jewel is made of pure gold (24 carats).
- Pisces: Indicates that the jewel is made of 585 thousandths gold (14 carats).
- Clover: Means that the jewel is made of 375-thousandths gold (9 carats).
- Shell: Indicates that the jewel is made of 585 thousandths gold (14 carats).
These hallmarks are affixed by guarantee offices after verification of the jewel's gold content. They guarantee that the jewel complies with current legal standards.
A ring with a "750" hallmark indicates that it is made of 75% pure gold (18 carats). Check the hallmark on the inside of the ring.
Pure gold is not magnetic. If your jewelry is attracted to a magnet, it probably contains non-precious metals. This test is quick and easy, but not infallible,
because some gold alloys may also contain non-magnetic metals. However, it is a good first indicator.
Steps :
- Bring a powerful magnet (such as a neodymium magnet) close to the gold jewel.
- If the jewel is attracted to the magnet, it probably contains magnetic metals, which means it's not pure.
Advantages :
- Simple, fast and non-destructive.
Disadvantages :
- This test only eliminates magnetic metals, but some non-magnetic alloys can still imitate gold.
Genuine gold jewelry does not tarnish easily. If you see traces of tarnish or changes in color, the jewelry may be plated.
Rub the surface lightly with a soft cloth; wear of the gold layer may reveal a different base metal underneath. Lower-carat gold alloys may tarnish over time
tarnish over time, but not in the same way as non-precious metals.
A ring that shows black spots or areas where the gold color has faded to reveal silver metal underneath is probably a plated ring.
Rub the jewel on an unglazed ceramic surface. If a yellow trace appears, it's a good sign that the jewel is made of gold.
Caution: this test may slightly damage the surface of the jewel. Use a ceramic plate specially designed for this test.
Rub your gold pendant on an unglazed ceramic plate; if it leaves a yellow trace, it's gold-plated.
The bite test is one of the oldest and most popular methods of checking whether a piece of jewelry is genuine.
Since pure gold is a soft metal, it is possible to leave a slight impression with the teeth by biting gently.
However, this technique can damage the jewel and is not 100% reliable, as lead plating or, for example, would react in a similar way.
Steps :
- Gently bite the jewel, exerting gentle pressure.
- If teeth marks appear, this may indicate that the jewel is made of gold (or plated lead, beware of this imitation).
Advantages :
- Quick and easy method.
Disadvantages :
- Unreliable and can damage the jewel.
- Lead or plating would react in the same way, giving a false positive result.
Gold is a dense, heavy metal. Genuine gold jewelry will therefore be heavier than its less dense imitation alloys.
If you have the opportunity to compare a piece of jewelry you suspect to be made of or with another that is similar in appearance but which you know to be made of gold, you can be sure that it is made of gold.
The density test involves measuring the mass of the jewel and dividing this mass by the volume of water displaced when the jewel is immersed in a water-filled container.
The density of pure gold is 19.3 g/cm³, while that of other metals is generally lower.
This test can be carried out at home using an accurate balance and a graduated container, but is often more reliable when performed by a professional.
Steps :
- Dry-weigh the jewel to determine its exact weight in grams.
- Immerse the jewel in a container of water filled to a precise level.
- Measure the volume of water displaced by the jewel (in millilitres). This volume represents the volume of the jewel.
- Calculate the density by dividing the mass of the jewel by the volume of water displaced.
Reference density :
- Pure gold (24K ): approx. 19.3 g/cm³
- Or 18K: between 15.2 and 16.9 g/cm³.
- Or 14K: between 12.9 and 14.6 g/cm³.
- Or 9K: approx. 11 to 12.8 g/cm³.
Advantages :
- Non-destructive and fairly reliable method.
Disadvantages :
- Requires precise equipment (scales and graduated container).
- Less accurate than chemical tests for complex alloys.
Electronic gold testers are modern tools for measuring the metal's conductivity, which varies according to its purity. They are accurate and easy to use.
Steps :
- Place a probe on the surface of the jewel.
- The tester measures conductivity and displays purity in carats or po
urcentage.
Advantages :
- Very precise.
- Non-destructive and fast.
Disadvantages :
- Electronic testers are relatively expensive and often used by professionals.
X-ray fluorescence spectrometry is a professional method for analyzing the exact chemical composition of a metal.
It is used by jewelers and refiners to obtain an extremely precise analysis of gold content.
Advantages :
- Very precise results.
- Complete analysis of all metals present in the alloy.
Disadvantages :
- Requires sophisticated equipment.
- High cost, not accessible to the general public except for professionals.
Does a piece of jewelry always have a hallmark?
No, gold doesn't always have a hallmark. While the presence of a hallmark is the most common and reliable way to identify a piece of gold jewelry, it's important to know that not all gold jewelry is hallmarked.
for several reasons:
No hallmark on handcrafted or antique jewelry
Handcrafted jewelry is often made by hand, and the absence of a hallmark is relatively common for several reasons:
- Lack of regulation
- Independent craftsmen, who create jewelry in small quantities or to order, are not always subject to the same strict regulations as the major jewelry houses.
In some cases, the craftsman may not have the means or equipment to hallmark each piece.
- Small-scale production
- When jewels are made in small series or are one-off pieces, the craftsman may find it unnecessary to affix a hallmark.
He may also omit this step due to a lack of resources or constraints.
- Flexible materials
- Craftsmen may also use gold alloys or other metals in varying proportions, making it difficult or inconsistent to apply a standard hallmark.
Antique jewelry
Antique jewelry, especially that made before modern regulations were introduced, may also be unmarked. This may be due to
- Different historical regulations
- In some historical periods or regions, hallmarking was not as strictly regulated as it is today.
In medieval Europe or before the 19th century, for example, laws on the marking of gold jewelry varied enormously from country to country and locality to locality.
- Wear and tear of time
- Very old or frequently worn jewelry may have lost their hallmarks over time. Hallmarks are often engraved in discreet places (inside of a ring, clasp of a necklace),
which can be subject to wear and tear.
- Repairs or modifications
- Antique jewelry may have undergone repairs or modifications over the years.
For example, an antique ring may have been enlarged, or a necklace clasp replaced, which could have erased the hallmark or moved part of the jewel that bore it.
- Less standard punches
- At certain times, hallmarks were less standardized and uniform than they are today.
It's possible that an antique piece of jewelry may have been hallmarked in a way that doesn't conform to modern standards, or that the hallmark isn't immediately recognizable as
- Family jewelry or jewelry handed down through the generations
Jewelry that has been passed down from generation to generation, especially within families, may not have a hallmark, as it was often made in a more personal and less commercial setting:
- Family heritage:
- Symbolism rather than commercial value:
- Foreign jewelry
In some countries, hallmarking regulations are not as strict as in Europe or North America.
As a result, jewelry made abroad, especially in regions where the gold trade is more informal or where local craftsmanship is favoured, may not bear a
- Jewelry bought in local markets or by artisans abroad may not be subject to the same rules as jewelry bought in a regulated jewelry store in the West.
- Jewel wear
- Over time, jewelry can become worn, which can partially or totally erase the hallmark. This is particularly common on older or frequently worn pieces, such as
- Fake gold jewelry
- Some gold jewelry, especially counterfeits or imitations, may be sold without a hallmark or with a false hallmark. This may be an attempt to deceive the buyer.
What should I do if a piece of gold jewelry doesn't have a hallmark?
The absence of a hallmark does not necessarily mean that the jewel is not gold, but it should encourage caution. Here are a few recommendations:
- Perform additional tests:
- Call in a professional:
Although the hallmark is a reliable indicator of gold purity, its absence is not a definitive sign that the jewel is not gold.
It simply means that extra vigilance and other methods are required to confirm authenticity.