Unlocking the Secret of Diamond Overtones: What Most Jewellers Won’t Tell You

24 November 2025 • 3 min read

When it comes to diamonds, everyone loves to talk about the Four Cs: carat, colour, clarity, and cut. But there’s a lesser-known factor that can influence a diamond’s beauty: the diamond  overtone. Once you understand what an overtone is, you’ll have a whole new perspective on choosing the perfect diamond.

What Exactly Is a Diamond Overtone?

In simple terms, an overtone is a subtle secondary hue that a diamond can have. It’s not something you’ll find on a grading certificate like the ones from GIA, but it’s definitely something that can affect how a diamond looks in real life. Overtones can come in shades like brownish, greenish, or even a milky haze.

Why Overtones Matter

How Overtones Affect a Diamond’s Sparkle

Overtones are important because they can influence a diamond’s brilliance, dispersion, and overall sparkle. In other words, even a diamond with a top-tier colour grade can look a bit less lively if it has a noticeable overtone.

A Real-Life Comparison

Imagine you have two round brilliant diamonds that are identical in carat weight, colour, and clarity. They’ve both got the same cut, polish, symmetry, and even the same kind of grading certificate. On paper, they should look identical. But when you see them in person, one diamond might appear more brilliant and lively simply because it doesn’t have that subtle overtone dulling its sparkle.

Why You Should See Diamonds in Person

This is exactly why we recommend seeing diamonds in person rather than just relying on certificates or online listings. At Ernesto Buono Fine Jewellery, we have a wide range of loose diamonds that you can compare side by side. That way, you can really see these nuances and pick the diamond that looks the most stunning to you.

Conclusion

In conclusion, understanding diamond overtones can give you a real edge in selecting a truly brilliant stone. While certificates and grades are important, nothing beats seeing a diamond in person and noticing how these subtle characteristics come into play. We invite you to visit Ernesto Buono and explore our collection firsthand because the perfect diamond is the one that delights your eyes in real life.

FAQs About Diamond Overtones

1. What is a diamond overtone?
A diamond overtone is a subtle secondary hue that can affect the stone’s overall appearance and sparkle.

2. Are overtones included on a GIA certificate?
No, overtones are not mentioned on standard diamond grading certificates.

3. How can I spot an overtone in a diamond?
The best way is to view the diamond in person and compare it against other stones under good lighting.

4. Do overtones affect the value of a diamond?
Yes, diamonds with strong overtones can sometimes be less valuable because they may appear less brilliant.

5. Why is it important to see a diamond in person before buying?
Seeing a diamond in person helps you notice any overtones or other subtle characteristics that might not be visible in photos or on paper.