Is every inclusion a flaw?
Not really. In gemology, some inclusions do the exact opposite of what most buyers think.
They don’t reduce value—they confirm authenticity.
Let’s break that down.
What Are Inclusions?
- Inclusions are features trapped inside a gemstone.
- They can be solid, liquid, or gaseous.
- You see them as feathers, needles, clouds, fingerprints, bubbles, or veils.
- Some are eye-visible. Some need magnification.
But here’s the key point:
Not all inclusions are bad. Some are useful. Some are beautiful. Some are proof.
Inclusions That Prove a Gem Is Natural
1. Three-Phase Inclusions in Colombian Emeralds
- These contain a gas bubble, a liquid, and a tiny crystal.
- Found only in natural emeralds from certain Colombian mines.
- Impossible to fake convincingly in synthetics or glass.
- If you see one, you’re looking at a true geological product—not a lab-grown copy.
2. Silk in Sapphires
- Fine needles of rutile aligned in a pattern.
- When undisturbed, they create a soft glow—often called velvety.
- Most visible in untreated sapphires from Sri Lanka and Kashmir.
- Heat treatments often melt silk. Its presence usually signals no heating.
- So if you see silk, you’re likely holding an unheated sapphire—something collectors value.
3. Horsetail Inclusions in Demantoid Garnet
- Radiating fibers that resemble a horsetail.
- Specific to Russian Ural demantoids.
- A geographic fingerprint. Not just a clue—it’s an origin marker.
4. “Fingerprint” Inclusions in Rubies
- Resemble smudges or fingerprints under magnification.
- Often form when the crystal heals from natural fractures.
- Common in natural rubies, rare in synthetics.
Why Buyers Get It Wrong
You’ve likely been told that flawless gems are more valuable.
That’s only partially true.
In diamonds, clarity plays a bigger role.
But in colored stones, origin and treatment status often matter more.
Ask yourself:
- Would you prefer a flawless synthetic ruby from a lab in Bangkok?
- Or a natural ruby with minor inclusions from Mogok, Burma?
Collectors and dealers know the answer.
Inclusions vs Treatments
- Some inclusions disappear after heat or clarity treatments.
- Others are created artificially in flux-grown synthetics.
- A skilled gemologist knows the difference.
- So should you.
What You Should Look For
When buying colored stones:
- Ask for a gem report from a trusted lab.
- Use a loupe or microscope if you can.
- Don’t reject a gem just because it has inclusions.
- Ask what the inclusions tell you about the stone’s history.
A Personal Note
I’ve seen buyers walk away from beautiful Kashmir sapphires because they spotted silk.
Others rejected Colombian emeralds because of “flaws” that were actually three-phase inclusions.
They weren’t rejecting flaws.
They were rejecting proof.
Final Thought
The next time you see a tiny inclusion in a gem, pause.
Ask:
Is this a flaw?
Or is it a signature from the Earth itself?
