When selling gold or diamond jewelry, it’s natural to wonder how buyers determine its value. Unlike everyday purchases, selling precious items involves technical testing, close inspection, and professional grading. Jewelry buyers use a combination of tools, techniques, and experience to ensure what you’re selling is genuine and priced fairly. So, how exactly do they test gold and diamonds?
Gold Testing: Verifying Purity and Authenticity
1. Visual Inspection
The evaluation begins with a simple but experienced eye. Jewelry buyers first inspect the piece for any official markings or stamps indicating karat value—such as 10K, 14K, 18K, or 22K. They’ll also look for signs of wear that might reveal whether a piece is gold-plated rather than solid gold.
2. Magnet Test
Real gold is not magnetic. A magnet test helps determine if other metals are mixed in or if the item is simply gold-plated over a magnetic base. While it’s not conclusive on its own, this quick test gives an early indication of authenticity.
3. Acid Test
A widely used method involves applying nitric acid to a small scratch made on the jewelry’s surface. Different acid strengths correspond to different gold purities. The reaction—whether the metal dissolves or stays unchanged—helps determine the karat level. This test is typically done on a discreet part of the item or a testing stone to avoid damaging the piece.
4. Electronic Gold Tester
For a non-destructive and precise reading, many buyers use electronic gold testers. These devices send a small electrical current through the metal and measure the resistance, which varies with gold content. It’s fast, clean, and accurate, especially when dealing with mixed or unmarked pieces.
Diamond Testing: Judging Authenticity and Quality
1. Thermal Conductivity Test
Real diamonds conduct heat differently from most fakes. A diamond tester uses thermal conductivity to detect if a stone is genuine. When the probe touches the stone, it quickly analyzes the rate of heat transfer and gives an instant reading—genuine or imitation.
2. UV Light Inspection
Under ultraviolet (UV) light, some diamonds fluoresce in a characteristic way. While this isn’t a definitive test, it can help distinguish real diamonds from certain fakes, especially moissanite, which may behave differently under UV exposure.
3. Loupe and Microscope Examination
Jewelry buyers often examine diamonds under a jeweler’s loupe or microscope to check for internal flaws (inclusions) and surface blemishes. These observations help assess the diamond’s clarity grade. They also look at the cut and symmetry, both of which impact the diamond’s overall brilliance and value.
4. Certified Grading Comparison
If a diamond is accompanied by a grading certificate (from GIA, IGI, etc.), buyers compare the stone to the report to ensure consistency. Certified stones typically fetch higher prices because the quality is verified by a third-party authority.
In many cases, professional buyers like G Luxe jewelry buyers combine advanced tools with years of hands-on experience to evaluate both gold and diamonds accurately. Their approach ensures that sellers receive honest assessments backed by industry-grade techniques and standards.
Why Accurate Testing Matters
Whether you’re selling a family heirloom or an unused ring, proper testing ensures you get paid for what the item is truly worth. It also builds trust between sellers and buyers, especially in an industry where authenticity is everything. Good buyers are transparent, explain their methods, and walk you through the process step by step.
Conclusion
Testing gold and diamonds isn’t just about price—it’s about precision, trust, and transparency. From acid tests and magnet checks to thermal probes and microscopes, jewelry buyers use a blend of science and expertise to evaluate each piece. So the next time you consider selling your valuables, know that professional buyers follow a rigorous process to ensure both parties walk away satisfied.