Introduction

Ever wondered if moissanite could fool a diamond tester? You’re not alone. Plenty of people buy moissanite for its stunning sparkle and budget-friendly price, but then comes the big question—can it pass as a diamond?

The short answer: sometimes.

Moissanite shares some key traits with diamonds, and older testers can get tricked. But newer technology? Not so much. If you’re planning to test moissanite with a diamond tester, there are a few things you should know first.

Experts have tested moissanite against diamonds for years, and the results always depend on the tool being used. Some testers are easy to fool, while others will call it out in seconds. Let’s break down exactly what happens when moissanite meets a diamond tester.

Does Moissanite Pass a Diamond Tester?

It depends on the type of tester.

Diamond testers work by measuring thermal conductivity or electrical conductivity. Moissanite and diamonds conduct heat in a similar way, which means older testers—those that rely only on heat—can mistake moissanite for a diamond.

But here’s where things get interesting. Diamonds conduct electricity, while moissanite doesn’t. Newer testers that check for electrical conductivity will spot the difference instantly.

So, if you’re using a basic heat-based tester, moissanite might pass as a diamond. But if you’re using an advanced tester? No chance.

Why Does Moissanite Fool Some Diamond Testers?

Moissanite is sneaky. It has a lot in common with diamonds, and one of its best tricks is heat conductivity. Older diamond testers rely on heat to tell if a stone is real, and since moissanite conducts heat almost as well as a diamond, these testers can get confused.

But diamonds have another superpower: electrical conductivity. Moissanite doesn’t conduct electricity the same way, which is why newer testers that check for both heat and electricity will expose it immediately.

If a moissanite passes a diamond tester, it’s not because the stone is trying to be something it’s not—it’s because the tester is only looking at half the picture.

How to Accurately Test for Moissanite vs. Diamond

If you really want to know whether a stone is moissanite or a diamond, don’t rely on just one test. Some methods work better than others:

• Use a multi-tester. The best diamond testers check both heat and electrical conductivity. If the stone doesn’t conduct electricity, it’s moissanite.
• Look at it under a loupe. Moissanite has double refraction, meaning you might see doubled-up facet edges inside the stone. Diamonds don’t do that.
• Try UV light. Some moissanites glow differently under UV compared to diamonds, but this isn’t foolproof.
• Check the fire. Moissanite has a more colorful sparkle than a diamond. If it throws off a rainbow light show, that’s a clue.
• Go to a jeweler. A professional can test the stone properly and confirm what it is.

If you want 100% certainty, a gem lab can give an official grading report. Otherwise, a good tester and a trained eye should do the trick.

Frequently Asked Questions

Can jewelers tell the difference between moissanite and diamond?

Yes, and pretty quickly. Jewelers look for clues like double refraction, extra colorful sparkle, and the way light moves through the stone. With a loupe and a little experience, it’s usually easy to spot the difference.

Will moissanite test as a diamond on all testers?

No. It might pass on older testers that only check heat conductivity, but newer multi-testers that check electrical conductivity will catch it every time.

Does moissanite pass a diamond tester at a pawn shop?

It depends on the tester they use. Some pawn shops still use older heat-based testers, which could mistake moissanite for a diamond. But many shops now use advanced testers, so it’s hit or miss.

What’s the easiest way to tell if a stone is moissanite or diamond?

Check the sparkle. Moissanite has more colorful flashes of light than a diamond. If the stone throws off rainbows like a mini disco ball, there’s a good chance it’s moissanite.

Conclusion

So, does moissanite pass a diamond tester? Sometimes, but not always. If you’re using an older heat-based tester, moissanite might fool it. But if you use a modern tester that checks for electrical conductivity, moissanite won’t stand a chance.

If you’re unsure about a stone, don’t rely on just one test. A loupe, a multi-tester, or a professional jeweler can tell you what you’re dealing with. And if you love the sparkle, does it really matter? Moissanite and diamonds both shine—just in their own way. Shop for a dream moissanite engagement ring at Barkev’s, save money without compromising on quality or sparkle.