You've received your ring. It's beautiful. But a question lingers: how do I actually know this is moissanite and not something else? This is a reasonable question — and there are clear, definitive answers. Here are the methods, in order from simplest to most conclusive.
Method 1: Check Your GRA Certificate
Every legitimate moissanite from a reputable seller arrives with a GRA (Gemological Research Association) certificate. This document specifies: the stone's weight in carats, its color grade (DEF colorless, or GHI near-colorless), its clarity grade (VVS1, VS1, etc.), and a unique certificate number. If you have a GRA certificate, verify the certificate number directly with GRA. The certificate number is the single most reliable post-purchase confirmation available without specialist equipment.
At Moissanite Shine, every stone ships with a verifiable GRA certificate documenting DEF color and VVS1 clarity. If your seller did not provide a certificate, that is itself important information about the seller.
Method 2: The Double Refraction Test (Loupe or Jeweler's Loupe)
Moissanite has a property called birefringence — it is doubly refractive, meaning it splits light into two rays as it passes through the stone. Under a 10x jeweler's loupe, this is visible as a doubling of the back facet edges when you look through the table (flat top) of the stone. You will see each facet edge appear as a double line rather than a single line.
Diamond is singly refractive — it does not show this doubling. Cubic zirconia is also singly refractive. If you see facet doubling under magnification, your stone is moissanite (or another doubly refractive stone, though most common simulants are not). If you do not see doubling, additional testing is needed.
Method 3: Dual-Mode Diamond Tester
Standard single-mode diamond testers measure thermal conductivity. Moissanite has unusually high thermal conductivity — high enough that older single-mode testers register it as "diamond." This is actually a positive indicator of moissanite, not a problem. However, the definitive test uses a dual-mode tester that measures both thermal conductivity AND electrical conductivity. Moissanite conducts electricity; diamond does not. A dual-mode tester will positively identify moissanite as "moissanite" rather than "diamond" or "non-diamond."
Most professional jewelers have dual-mode testers. If you want a definitive electronic confirmation, a brief visit to a local jeweler with this equipment is the fastest route.
Method 4: Visual Inspection — Rainbow Fire
Moissanite's dispersion (0.104) is 2.4 times higher than diamond's (0.044). In direct sunlight or under a bright light source, move the stone slowly and observe the fire it throws. Moissanite produces vivid, colourful rainbow flashes significantly more intense than a diamond of the same size. If the stone looks unusually brilliant and fiery compared to what you expected, that is consistent with moissanite's optical properties.
This method is confirmatory but not conclusive — it tells you the stone has high optical performance, but a high-quality CZ when new can also be visually impressive. Use it alongside other methods.
Method 5: Professional Gemological Testing
For absolute certainty, a certified gemologist with a spectroscope can conclusively identify moissanite by its spectral absorption pattern — a unique optical fingerprint that no other stone shares. This is the gold standard of gemstone identification and is available at any GIA-certified gemological lab or experienced local appraiser.
What If I'm Concerned?
If you purchased from Moissanite Shine and have any question about your stone's authenticity, contact us directly. We stand behind every stone we sell with a lifetime warranty and full transparency about sourcing and certification. We will assist you in arranging any verification you need.
Related reading:
GRA Certificate Explained: What It Is and How to Verify Yours
Moissanite Birefringence: The Truth Behind Double Refraction
Does Moissanite Pass a Diamond Tester?