In a world where precious metals like gold are highly sought after, the proliferation of imitations and counterfeits has become increasingly prevalent. From jewellery to investment bars, distinguishing between genuine yellow metal and its convincing replicas can be a challenging task for the untrained eye. However, aurum’s unique properties lend themselves to specific testing methods that can reveal its authenticity. This guide will explore various techniques to differentiate genuine gold from its less expensive imitations, providing insights into the tools, methods, and indicators that make the task not as daunting as it may seem.
There are several metals that have a similar outward appearance to gold. Distinguishing between genuine gold and just some yellow metal can sometimes seem difficult, but it is not as difficult as it might seem. Here are some useful tips on how to do it:
Most frequently, less expensive metals like brass, copper, tungsten, or other metals are used to imitate fine gold. These materials can be over-gilded or coloured to look as much like precious metal as possible. However, compared to other metals, the noble metal has properties that help to clearly distinguish it from other metals and identify whether it is genuine or not.
Genuine Gold Does Not Tarnish
Today, there are a number of quite sophisticated counterfeiting techniques that generally require an expert’s eye and equipment. In the case of electroplating, for example, it is quite difficult to tell by eye whether or not the metal is real. However, in the case of slightly inferior forgeries, it is possible to recognise a forgery by external observation. Genuine gold is dense, heavy, and does not tarnish or corrode. Counterfeit gold may appear yellower and lighter. It may be dull and flaky or uneven in colour.
When looking for gold jewellery, it is always worth looking for the gold sample number, which indicates how much of the metal alloy used to make the item is gold. For example, gold bracelets and necklaces are mainly made with a sample of 375 or 9 carats, 585 or 14 carats, and 750 or 18 carats. The pure gold standard is 999, which means that the object is made of 99.9 percent gold.
It should be noted that it is also possible to counterfeit a gold sample, which means that the stamp of the sample number on the piece of jewellery does not fully authenticate it.
Magnets and Acids
If in doubt, the metal can also be tested in several ways. For a start, try using a magnet. Gold is non-magnetic, so it should not react to a magnet. If you place a magnet near a gold metal and it attracts the magnet, it is probably made of another metal or alloy.
Gold is a dense metal, which means that even small pieces are quite heavy. Try comparing its weight with another piece of metal of a similar size, or with another piece of gold. However, it is also worth bearing in mind that fraudsters may add other high-density metals to the melt to simulate the weight of gold.
It is also possible to check the authenticity of gold using an acid test, a chemical method in which a small amount of acid is added to the metal. The reaction that follows indicates the purity of the gold, as different acid solutions are used for different samples. However, it is wise to leave the acid test to the professionals, as it requires special solutions and proper use.
Scraping and Filing Techniques for Identifying Authentic Gold
Scraping can be carried out for easy identification of the rolled-over jewellery. This can be done by filing or scraping the jewellery to be examined against a stronger surface. For example, the bottom of a ceramic mug or plate can be used, and it can be observed whether the material scraped off the top of the jewel is the same colour as the jewel itself.
In addition, it is possible to look deeper than the top layer of the jewellery and examine whether the scratched area on the jewellery is the same colour as the surface of the jewellery. If, when scraping or slicing, it is apparent that the scraped area is a different colour to the surface of the jewel, it is possible to suspect that the jewel has been over-mounted.
Gold has a density of 19.3 g/cm³, which is higher than most other metals. Density is given by the ratio of mass to volume. It is therefore possible to determine whether the gold is pure gold (sample 999) or not, even with home equipment.
To do this, you need to take an object made of gold and weigh it as accurately as possible, for example, using a kitchen scale. The next step is to determine the volume, which can be done by immersion. A volumetric funnel should be taken with the volume in millilitres marked on it. Fill the container with water and write down the initial reading. The next step is to submerge the object in water (the gold object will certainly sink to the bottom) and record the new reading. Subtract the new reading from the original reading to obtain the volume of the object.
Make sure that the units are correct before proceeding with the calculations. Millilitres can be converted into cubic centimetres (1 ml = 1 cm³) and grammes can be used as the unit of mass of the object. The final calculation is to divide the mass (in grammes) by the volume (in cubic centimetres) to obtain the density. In the case of pure gold, the density is 19.3 g/cm³.
Determination of gold using X-ray fluorescence spectroscopy (XRF)
XRF is a method that uses X-rays to determine gold. X-rays are applied to the object to be examined, which causes the atoms in the material to enter an excited state (the electron in the inner layer of the atom absorbs energy and leaves the atom). Since the excited state is unstable, the electron in the outer layer of the atom falls to a lower energy level, (replacing the electron that left the atom). The process that takes place is relaxation, which releases energy – in the form of fluorescence radiation – that is characteristic of a particular atom. By measuring this released radiation, it is possible to determine the gold content and identify other elements used in the alloy.
So there are several ways of finding out whether it really is gold or an imitation. If in doubt, it is always worth seeking the advice of a professional jeweller, goldsmith, or other expert who has the equipment and knowledge to identify the material without a doubt.
The allure of gold has led to the creation of various counterfeiting methods, each with its challenges and detection techniques. While some may require professional tools and expertise, others can be conducted at home with basic equipment. From magnets and acids to XRF technology, the means to authenticate gold are diverse and accessible. Whether it’s personal jewellery or a potential investment, understanding these methods provides invaluable assurance in the integrity of the gold in question. When in doubt, professional jewellers and goldsmiths stand ready to lend their expertise, safeguarding against the pitfalls of counterfeit gold. In an age where appearances can deceive, knowledge and vigilance remain the golden keys to authenticity.