How to Tell if a Diamond is Real or Fake: Expert Guide (2026)

90% of people cannot tell the difference between a Real and a fake diamond. Here’s how to do it correctly.
Buying a diamond is a meaningful investment. And there’s one question that comes up every single time:
What are the key ways to verify if a diamond is authentic?
With the rise of lab-grown diamonds and high-quality imitations, understanding diamond authenticity is more important than ever.
This guide explains what works and what doesn’t.

• Real vs Fake Diamonds: What You Need to Know
  Before testing anything, understand this clearly:
  Real diamonds: Natural and lab-grown
  Fake diamonds: Cubic zirconia, glass, or other simulants
   Important: Lab-grown diamonds are 100% real diamonds.
   They have the same brilliance, hardness, and structure as natural ones.
   Read more:
    Lab-Grown vs Natural Diamonds → /blogs/lab-grown-vs-natural-diamonds

 Visual Comparison

•  Real vs fake diamond comparison: How Experts Check if a Diamond is Real
  Professionals don’t rely on basic tricks. They use precise methods:
  1. Thermal Conductivity Test
  Diamonds disperse heat instantly.
   Jewellers use diamond testers to measure this accurately.
  2. Electrical Conductivity Test
  Used to separate diamonds from moissanite.
  3. Microscopic Examination
  Experts check:
  Natural inclusions
  Growth patterns
  Internal structure
   This is the most reliable way to confirm diamond authenticity.
• Diamond Tests at Home (And Their Limitations)
  Many people search for “diamond test at home”, but these are not fully reliable:
  Water Test
  Real diamonds usually sink.
   But some fake stones can also behave the same.
  Fog Test
  Real diamonds clear quickly.
   But humidity and temperature can affect results.
  Newspaper Test
  Refraction blurs text, but cutting and setting matter.
   These tests can give clues, but they are not proof.
•  How a Real Diamond Reflects LightA real diamond doesn’t just shine, it performs with precision:
  Bright white brilliance
  Controlled rainbow flashes
  Sharp reflections
  Fake stones often:
  Look glassy
  Show excessive rainbow colours
•  Certification: The Only Reliable Proof
  The most accurate way to check if a diamond is real:
  ✔ IGI Certification
   ✔ GIA Certification
  These confirm:
  Authenticity
  Cut, clarity, carat
  Origin (lab or natural)
•  How to Ensure You’re Buying a Real Diamond?
  Always ask for certification
  Buy from trusted brands
  Avoid unrealistic pricing
  Check return & authenticity policies
  At AIVA Jewellery, every piece is crafted using certified diamonds and precision-led design.
   Explore our collection:
  Diamond Earrings → https://aivajewellery.com/collections/diamond-earrings
  Shop All Jewellery → https://aivajewellery.com/collections/all
•  Modern Buyer Insight (What Actually Matters)
  Instead of asking:
   “Is this diamond real?”
  Ask:
  Is it certified?
  Is the craftsmanship premium?
  Is the design timeless?
   That’s how informed buyers shop today.
•  Frequently Asked Questions
  Real or Fake. How can you tell the difference in a diamond?
  Basic tests like water or fog can help, but they are not fully reliable.
  Are lab-grown diamonds real or fake?
  Lab-grown diamonds are 100% real diamonds with identical properties.
  What is the most accurate way to test a diamond?
  Professional testing and certification (IGI/GIA) are the most reliable.
  Can fake diamonds look real?
  Yes, high-quality simulants can look similar but lack true diamond properties.

•  Conclusion
  Understanding how to tell if a diamond is real or fake requires more than simple tricks.
  While home tests can offer basic insights, the most reliable method is professional certification.
  When you choose AIVA Jewellery, you’re choosing authenticity, precision, and modern luxury.