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A preliminary assessment of a piece of jewelry doesn't always require complex equipment. You can start with two key tools that will help you draw initial conclusions about the authenticity of the stones and the overall condition of the piece. The basics of gemology for beginners start with knowing how to correctly use these simple instruments.
| Tool | Purpose | Note |
| Jeweler's Loupe (10x) | Examining internal inclusions in a stone, cut quality, and hallmarks on the metal. | The primary and most important tool for visual analysis. |
| Diamond Tester | Determining thermal conductivity for a quick check of a diamond's authenticity. | Effective against simple imitations, but can give a false positive for moissanite. |
A preliminary assessment of a piece of jewelry doesn't always require complex equipment. You can start with two key tools that will help you draw initial conclusions about the authenticity of the stones and the overall condition of the piece. The basics of gemology for beginners start with knowing how to correctly use these simple instruments.
The main tool for any jeweler and appraiser is a jeweler's loupe. The standard is ten-power (10x) magnification. When using a loupe, it's important to hold it as close to your eye as possible, and then bring the item closer until the image is in focus. This allows for a detailed examination of the stone's internal structure, its cut features, and the condition of the metal and hallmarks.
The second useful device is a diamond tester. This is an electronic tool that measures a stone's thermal conductivity. Since diamonds have uniquely high thermal conductivity, the tester easily distinguishes them from most imitations, such as cubic zirconia or glass. However, it's worth remembering that some modern synthetic stones, like moissanite, can fool simple testers, so its readings should be considered in conjunction with other signs.
Once you have mastered these tools, you can move on to a more in-depth analysis of the characteristics of stones and metal, which will significantly increase your confidence when appraising jewelry.
One of the main questions in an appraisal is how to distinguish a natural stone from a synthetic one. Natural minerals, formed over millions of years underground, almost always have unique internal features that serve as their 'fingerprint.'
Under a loupe, you can often see various inclusions in natural stones: microscopic fractures, gas or liquid bubbles, or other small crystals. These 'imperfections' are evidence of natural origin. Synthetic counterparts, grown in a laboratory under ideal conditions, are most often perfectly clean and transparent. Their flawlessness can actually be a sign of artificial origin.
Another important aspect is color distribution. In natural stones, coloration is rarely perfectly uniform. You might notice zones of more or less intense color, or growth bands. In synthetic stones, the color is typically unnaturally uniform and saturated.
The shape of a stone's cut can tell a lot about the age of a piece of jewelry. Before the advent of modern technology in the late 19th and early 20th centuries, stones were cut by hand, and these antique cuts have their own characteristic features. Knowledge of them helps in dating antique jewelry.
One of the most recognizable is the 'rose' cut. It has a flat base and a domed top covered with triangular facets. This shape was popular from the 16th to the 19th century and gives stones a soft, romantic shimmer in candlelight, but it lacks the brilliance of modern cuts.
Another common type is the Old European Cut or the Old Mine Cut, predecessors of the modern brilliant. They are characterized by a high crown, a small table, and a large, open culet (the bottom point of the stone, visible through the top). The facets on such stones are often asymmetrical, which indicates they were hand-cut.
The presence of such characteristics is a strong argument for the antique origin and historical value of a piece of jewelry.
| Purity System | Hallmark Example | Gold Content |
| Metric | 585 | 58.5% |
| Metric | 750 | 75.0% |
| Zolotnik | 56 | 58.3% (equivalent to 585) |
| Zolotnik | 72 | 75.0% (equivalent to 750) |
Determining the authenticity of the metal is just as important a part of the appraisal as analyzing the stones. The main source of information about a precious metal is the hallmark or fineness mark, which is stamped on the item by state assay offices.
In Russia and countries of the former USSR, the metric system of purity is most common. For example, the '585' hallmark means that the alloy contains 58.5% pure gold. In antique items from Tsarist Russia, you can find the zolotnik system, where a '56' zolotnik mark corresponds to the modern '585' mark.
In addition to the numerical purity designation, the hallmark includes the mark of the assay office. In Soviet times, this was a five-pointed star with a hammer and sickle; in modern Russia, it is the profile of a woman in a kokoshnik. Examining the shape and clarity of the hallmark with a loupe helps determine the manufacturing period and authenticity of the item.
If the hallmark is missing or worn off, other methods can be used, although they require caution. Professionals use acid-based reagents to determine purity, but this method is unsafe for home use. A simpler method is the magnet test. Precious metals are not magnetic, so if a piece of jewelry is attracted to a magnet, it is likely a fake or an item made of a non-precious alloy with a thin gold plating.
