Moissanite has become a hugely popular diamond alternative, admired for its brilliance, durability, and budget-friendly echo of diamond. But when it comes to diamond testers—those handheld pens jewelers use—can moissanite really pass as a diamond?
In this post, we’ll dive into how diamond testers work, whether moissanite can trick them, and what that means for you when choosing a beautiful and ethical stone.
What Does a Diamond Tester Do?
Before we get into how moissanite performs, it’s important to understand how diamond testers work.
Most traditional diamond testers use thermal conductivity. Diamonds disperse heat quickly—faster than most gemstones. So, if a stone conducts heat well, the tester reads it as a diamond.
But here’s the twist: moissanite also conducts heat extremely well—so well, in fact, that it can register as a diamond on a basic thermal tester.
More advanced diamond testers, however, do something else: they also measure electrical conductivity. Diamonds are electrical insulators, while moissanite has mild conductivity. These dual testers can usually detect the difference.
Why Moissanite Often Fools a Tester
Let’s say your jeweler uses a pen-style thermal tester. Because moissanite shares a high thermal conductivity with diamond, it may produce a “diamond” reading even though it isn’t one.
This doesn’t mean you’re being misled—just that not all testers tell the whole story.
At Victoria Marie Jewelers, we use professional multi-testers that measure both thermal and electrical conductivity, giving us a more complete and accurate read on your stone. It’s part of our commitment to transparency and craftsmanship.
How Jewelers Identify
Experienced jewelers don’t rely on a single tool. Alongside conductivity testers, we use visual cues like:
Brilliance and fire – Moissanite has a more vibrant rainbow sparkle, often brighter than diamond.
Double refraction – Under magnification, moissanite can show a slight doubling of facets.
Faceting patterns – Moissanite is typically cut differently from diamond due to its unique optical properties.
If there’s ever doubt, advanced gemological tools (like a microscope or spectroscope) or professional gem labs can confirm the identity of a stone.
Should You Be Worried About Moissanite Passing?
Not at all.
Moissanite isn’t pretending to be a diamond—it’s a gorgeous gemstone in its own right. If it shows up as a diamond on a basic tester, it just means you’ve chosen a gem that holds its own when it comes to brilliance and quality.
At Victoria Marie Jewelers, we’re here to help you understand what you’re getting—whether it’s a natural diamond, lab-grown diamond, or high-grade moissanite—so you feel confident in every sparkle.
Why People Choose Moissanite
For many, moissanite isn’t just an alternative—it’s a preference. It offers:
Dazzling brilliance – In fact, it reflects more light than a diamond.
Exceptional durability – It ranks 9.25 on the Mohs scale, second only to diamond.
Cost-efficiency – You can get a larger stone without the diamond price tag.
Ethical appeal – Because moissanite is lab-created, it offers peace of mind for many shoppers.
Whether you’re designing an engagement ring, revamping a family heirloom, or looking for a dazzling pendant, moissanite delivers in style, performance, and value.
What to Ask When Shopping for Moissanite
If you’re considering a moissanite stone, ask your jeweler:
What kind of tester do you use?
Can I compare moissanite and diamond side by side?
Is this stone certified?
Can this be used in a custom setting? Our team at Victoria Marie specializes in helping you compare gemstones hands-on so you can decide what resonates most—with your style, your values, and your budget.
Can Moissanite Be Appraised or Insured? Yes. While moissanite doesn’t hold the same resale value as a natural diamond, it can be appraised and insured, especially when set in fine metal or custom jewelry. If you’ve chosen moissanite for your engagement ring or custom piece, we’ll help you get the appropriate documentation, whether you want to protect it for insurance or just for peace of mind.
Final Thoughts: Moissanite and the Diamond Tester Question
So, does moissanite pass a diamond tester?
Yes—if it’s a basic thermal tester.
No—if it’s a dual tester that includes electrical conductivity.
Either way—it’s a stunning choice.
At Victoria Marie Jewelers in Parker, CO, we believe every gem tells a story—and our job is to help you find the one that fits yours. Whether you’re drawn to the shimmer of a diamond or the fire of moissanite, our experienced team is here to guide you every step of the way.
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