Diamond tester: the rigour behind 35 years of expertise
A diamond tester is one of the tools we’ve relied on at La Puce d’Or, in Rosemont, for years. Here’s how it works, what it can actually confirm, and why it never replaces the eye of a jeweller and watchmaker.
Key takeaways
- An electronic diamond tester measures a stone’s thermal conductivity, and occasionally its electrical conductivity, to confirm it is indeed a diamond.
- No electronic test is foolproof on its own: some stones, such as moissanite, can throw off the result.
- At La Puce d’Or, the tester always works alongside the experience of our jewellers and watchmakers.
- This level of rigour, with more than 35 years of practice in evaluating and buying jewellery in Rosemont, supports this standard.
How does an electronic diamond tester work?
A diamond tester relies on a physical property well known to gemmologists: diamond conducts heat exceptionally well, better than nearly any other stone. The device applies a probe to the surface of the gem and measures how quickly the heat dissipates.
Some more advanced models also add an electrical conductivity reading, which helps rule out other imitations such as glass or white sapphire. The result appears within seconds, usually as a light or sound signal.
Why a single test is never enough
An electronic tester gives a quick indication, not a final verdict. Moissanite, an increasingly common synthetic stone, also conducts heat very well. It can therefore produce a result close to that of a diamond on a standard tester, which is why some more advanced models add a second, electrical test.
Some treated diamonds or certain settings can also throw off a single reading. That’s why our jewellers always examine the piece as a whole to determine its authenticity.
The tester: one tool among 35 years of know-how
Since 1991, La Puce d’Or has supported Montrealers in evaluating and buying back their jewellery. That longevity reflects a consistency in how we treat every piece that comes through our workshop.
A jeweller’s and watchmaker’s expertise is essential before relying on technology
The diamond tester backs up the examination carried out by our team. Unlike a simple gold-buying counter, our workshop brings together a jeweller and a watchmaker on site, able to recognize what no device can catch on its own: the cut, the visible inclusions under a loupe, and whether the stone matches its setting.
The evaluation process provides reassurance and offers protection
This double check, technological and human, serves a single purpose: making sure you leave with an honest evaluation, whether you’re selling a family piece or having a stone authenticated before a custom creation project.
Getting a diamond evaluated in Rosemont
Our workshop is located at 2960 Masson Street, in the heart of Rosemont, and is open seven days a week. Whether you’re weighing whether to sell an inherited piece or simply want to confirm a stone’s authenticity, an in-store visit remains the only way to get a reliable answer, at no cost and with no obligation.
Visit us for a no-obligation evaluation
Whether your diamond is inherited, recently found, or you simply want to verify its authenticity, our team is happy to answer your questions. We combine technology with 35 years of know-how to give you an honest evaluation, respecting the story that every piece of jewellery tells.
FAQ – Diamond testers and jewellery evaluations in Rosemont
How does a diamond tester work?
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It measures a stone’s thermal conductivity, and sometimes its electrical conductivity, to confirm it is a diamond. The result appears within seconds.
Is a diamond tester 100% reliable?
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No. It’s a useful first indicator, but some stones, such as moissanite, can throw off the result, which is why a follow-up examination by an expert matters.
Can a tester mistake a diamond for moissanite?
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Yes, simpler models that only measure thermal conductivity can mistakenly identify a diamond as moissanite. Devices that add an electrical conductivity test reduce this risk.
Can a diamond be tested while still set in a piece of jewellery?
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Yes, most electronic testers work without needing to remove the stone, which makes evaluating a ring or necklace easier.
Why does La Puce d’Or use an electronic tester?
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This rigour reflects the same philosophy that has guided our 35 years of expertise: providing a transparent evaluation supported by both technology and the knowledge of our jewellers and watchmakers.
Where can I get a diamond evaluated in Rosemont or Montreal?
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Our workshop at 2960 Masson Street, in Rosemont, offers this service on-site, with no appointment necessary, seven days a week.
Does the tester replace a jeweller’s expertise?
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No. The device confirms a physical property, but a complete evaluation of a diamond’s value always requires the eye and experience of a professional.
