Short answer: yes. Moissanite passes a standard thermal diamond tester — the pen-style tool most jewelers and pawn shops reach for first. It does not pass a dual moissanite/diamond tester, which measures electrical conductivity as well as heat. That's the whole story in two sentences. Here's why it matters.
Why moissanite passes a thermal tester
Standard diamond testers don't actually detect diamond. They measure thermal conductivity — how fast a stone pulls heat away from the probe tip. Diamond conducts heat exceptionally well, and so does moissanite. Cubic zirconia, glass, and white sapphire don't. So when the probe touches a moissanite stone, the tester reads "diamond" because the heat signature is nearly identical.
This is a physical property of silicon carbide, not a trick. It's also the fastest way to tell moissanite apart from CZ: CZ fails the tester instantly. Moissanite doesn't.
Why it fails a dual tester
Moissanite is slightly electrically conductive. Diamond (with rare exceptions) is not. A dual tester checks both heat and electricity, so it can separate the two in seconds. Professional jewelers, graders, and buyers use dual testers for exactly this reason.
What this means when you're buying
Three practical takeaways:
1. A passing thermal test proves it's not CZ. If a seller's "moissanite" fails a thermal tester, it's cubic zirconia or glass — walk away. Every Stone Blvd stone passes a thermal tester because every Stone Blvd stone is real silicon-carbide moissanite.
2. Nobody is fooled who doesn't want to be. A jeweler with a dual tester will identify moissanite in seconds. That's fine — moissanite isn't pretending to be diamond. It's a distinct gemstone with more fire (2× the dispersion of diamond), a 9.25 Mohs hardness, and a price that isn't propped up by a cartel.
3. Certification beats testing. Our GRA-certified pieces — like the GRA tennis bracelet — ship with grading paperwork stating exactly what the stone is: D color, VVS1 clarity, moissanite. No guesswork, no tester needed.
The honest position
We tell you this upfront because the sparkle doesn't need a cover story. Moissanite throws more colored fire than diamond, wears just as hard day-to-day, and costs 90% less. If someone tests your ring at a dinner party, the reading says "diamond." If a gemologist tests it in a lab, it says moissanite — and you paid rent with the difference.
See the stones for yourself: rings, tennis bracelets, and fully iced pieces — all D-color, VVS1, free shipping.