Lab Diamond Post Growth Treatment Explained: What IGI Certificates Really Mean

Shopping for a Lab Grown Diamond Often Means Comparing More Than the 4CS. Many Buyers Eventually Notice a Small Note on an Igi Certificate Mentioning Lab Diamond Post Growth Treatment. That Single Sentence Creates a Surprising Amount of Confusion Because Most People Have Never Heard of It Before.

The Good News is That Post-growth Treatment is a Normal Part of Manufacturing for Many Cvd Lab Diamonds. It is Fully Disclosed on Grading Reports and Does Not Make the Diamond Fake or Unstable. Instead, It is a Controlled Process Used to Improve Color After the Crystal Has Finished Growing.

If You Understand Why This Treatment Exists, How to Recognize It on a Grading Report, and What It Means for Value, You Can Compare Diamonds With Much Greater Confidence. This Guide Explains Everything in Simple Language While Helping You Understand What the Notation on an IGI Certificate Actually Means.

What is Lab Diamond Post Growth Treatment?

Lab Diamond Post Growth Treatment is a Finishing Process Performed After a Cvd Diamond Has Completed Its Growth Cycle.Lab Diamond Post Growth Treatment.

During the CVD Manufacturing Process, Some Diamonds Naturally Develop Slight Brown or Yellow Color Tones. While These Colors Are Often Extremely Subtle, They Can Prevent the Diamond From Achieving Premium Color Grades Like D, E or F.

Manufacturers Use High Pressure High Temperature (HPHT) Annealing to Reorganize Tiny Imperfections Inside the Crystal Structure. This Process Improves the Final Appearance Without Changing the Fact That the Stone is a Genuine Diamond.

Unlike Coatings or Surface Enhancements, Hpht Treatment Works Within the Crystal Itself. Once Completed, the Improvement Becomes Permanent.

For More Knowledge:  What is a Lab Grown Diamonds

Why Certain CVD Diamonds Require High Pressure Annealing

 Not Every CVD Diamond Requires Post-growth Treatment.

During Crystal Growth, Carbon Atoms Sometimes Arrange Themselves With Tiny Structural Defects That Create Faint Brown Coloration. Even Though the Diamond May Already Possess Excellent Clarity, These Color Centers Reduce Its Overall Grade.

High Pressure High Temperature Annealing Helps Remove Many of These Color Centers.
The Process Recreates Conditions Similar to Those Found Deep Inside the Earth Where Natural Diamonds Formed Millions of Years Ago. Extreme Heat and Pressure Allow Portions of the Crystal Lattice to Rearrange Into a More Colorless Structure.

The Result is a Brighter-looking Diamond Capable of Receiving a Higher Laboratory Color Grade.

Many Premium Lab Diamonds Sold Today Have Undergone This Process, Making It One of the Most Common Finishing Techniques Used Within the Industry.

Is Post Growth Treatment Safe?

Yes.
The Treatment Permanently Changes the Internal Atomic Arrangement of the Diamond
It Does Not Weaken the Crystal.

It Does Not Peel.
It Does Not Wear Away.
It Does Not Require Maintenance.

After Treatment, the Diamond Remains Chemically, Physically, and Optically Identical to Any Other Laboratory-grown Diamond.

Consumers Can Safely Wear Treated Lab Diamonds Every Day Without Worrying About the Color Fading Over Time.

How to Spot the Post Growth Treatment Notation on an IGI Cert

One of the Easiest Ways to Identify Treated Diamonds is by Reading the Comments Section of an IGI Grading Report.

Common Wording May Include:
"This Laboratory-grown Diamond Has Received Post-growth Treatment."

This Disclosure Allows Buyers to Know Exactly How the Diamond Reached Its Final Color Grade.

The Notation is Usually Found Near the Bottom of the Certificate Within the Comments or Additional Information Section.

When Shopping Online, Always Request the Complete Grading Report Rather Than Relying Only on Product Photographs.

A Transparent Seller Should Always Provide the Certificate Before Purchase.

Market Pricing Valuation Discrepancies for Treated Gems

Although Treated and Untreated Lab Diamonds Are Physically Identical, the Market Does Not Always Value Them Equally.

Untreated CVD Diamonds That Naturally Achieve Exceptional Color Grades Immediately After Growth Remain Relatively Uncommon. Because of This Rarity, Collectors and Certain Luxury Buyers Often Pay a Premium for Untreated Stones.

Meanwhile, Treated Diamonds Generally Offer Better Value for Everyday Consumers. Buyers Receive the Same Brilliance, Durability, and Beauty While Often Spending Less
For Engagement Rings, Most Shoppers Prioritize Appearance and Price Rather Than Whether the Diamond Received Post-growth Treatment.

This Creates an Excellent Opportunity to Maximize Beauty Within a Fixed Budget.

Treated vs Untreated Lab Diamonds

Feature	Treated	Untreated
Real Diamond	Yes	Yes
Chemical Composition	Same	Same
Hardness	10 Mohs	10 Mohs
Durability	Excellent	Excellent
Color Stability	Permanent	Permanent
Market Price	Usually Lower	Usually Higher
Collector Appeal	Moderate	Higher

 

Should You Avoid Treated Lab Diamonds?

Not Necessarily.

For Most Buyers, Post-growth Treatment Should Not Be Considered a Disadvantage.
Instead, Think of It as a Manufacturing Refinement Similar to Polishing After Cutting. The Diamond Remains Genuine, Durable, and Visually Stunning.

If Your Priority is Getting the Largest and Brightest Diamond Within Your Budget, Treated Lab Diamonds Often Provide Exceptional Value.

If You Specifically Want a Diamond That Achieved Its Color Naturally During Growth, You May Prefer an Untreated Stone, Though You Should Expect to Pay More.

Expert Buying Tips

Before Purchasing Any Lab Diamond:

• Always Review the Complete Grading Report.
• Check Whether Post-growth Treatment is Disclosed.
• Compare Identical Diamonds Before Making a Decision.
• Focus on Overall Beauty Rather Than Treatment Alone.
• Purchase From Reputable Jewelers Who Provide Certified Grading Reports.

A Well-cut Treated Diamond Frequently Appears More Beautiful Than a Poorly Cut Untreated Diamond.

Cut Quality Should Always Remain Your Highest Priority.

Conclusion

Post-growth Treatment is One of the Most Misunderstood Terms Found on Lab Diamond Certificates.

Rather Than Indicating a Lower-quality Diamond, It Simply Explains How the Manufacturer Improved Color After the Growth Process. The Treatment is Permanent, Scientifically Accepted, and Fully Disclosed by Respected Laboratories Like IGI.

Understanding This Notation Helps Buyers Compare Diamonds Fairly and Avoid Unnecessary Confusion. Whether You Choose a Treated or Untreated Lab Diamond, Focusing on Cut Quality, Certification, and Overall Appearance Will Usually Lead to the Best Long-term Purchase.

Frequently Asked Questions

Q.  What is Post Growth Treatment in a Lab Diamond?
A.  Post-growth Treatment is a High Pressure High Temperature (HPHT) Annealing Process Used on Some CVD Lab Diamonds to Remove Faint Brown or Yellow Tones and Improve the Diamond's Final Color Grade. The Treatment is Permanent and Fully Disclosed on Grading Reports.

Q.  Why Do Cvd Lab Diamonds Need Post Growth Treatment?
A.  Some Cvd Lab Diamonds Develop Slight Color Tint During the Growth Process. Post-growth Treatment Helps Reduce These Color Defects, Allowing the Diamond to Achieve a Higher Color Grade While Remaining a Real Diamond.

Q.  Does Post Growth Treatment Affect a Lab Diamond's Value
A.  Yes. Treated Lab Diamonds Are Usually Priced Lower Than Untreated Lab Diamonds With Similar Grades. However, Both Offer the Same Beauty, Durability, and Chemical Composition, Making Treated Diamonds an Excellent Value for Most Buyers.

Q.  Is a Post Growth Treated Lab Diamond a Real Diamond?
A.  Yes. A Post-growth Treated Lab Diamond is a Real Diamond Made of Pure Carbon With the Same Physical, Chemical, and Optical Properties as a Natural Diamond. The Treatment Only Improves Color.

Q.  How Can I Identify Post Growth Treatment on an Igi Certificate?
A.  Section of the IGI Grading Report. If the Diamond Has Received Post-growth Treatment, the Certificate Clearly States This, Ensuring Complete Transparency for Buyers.

Q.  Is HPHT Post Growth Treatment Permanent?
A.  Yes. HPHT Post-growth Treatment Permanently Changes the Diamond's Crystal Structure at the Atomic Level. The Improved Color Will Not Fade, Wear Off, or Change Over Time.

Q.  Are Untreated Lab Diamonds Better Than Treated Lab Diamonds?
A.  Both Are Genuine Diamonds With the Same Durability and Brilliance. Untreated Lab Diamonds Are Often More Expensive Because They Naturally Achieve High Color Grades Without Additional Treatment.

Q.  Should I Buy a Treated or Untreated Lab Diamond?
A.  If Your Goal is the Best Appearance for Your Budget, a Treated Lab Diamond is an Excellent Choice. If You Prefer a Diamond That Reached Its Color Naturally During Growth, an Untreated Lab Diamond May Be Worth the Higher Price.

Q.  Can Jewelers Detect Post Growth Treatment?
A.  Yes. Advanced Gemological Laboratories and Professional Jewelers Can Identify Post-growth Treatment Using Specialized Equipment. Reputable Grading Reports Also Disclose the Treatment.

Q.  Does Post Growth Treatment Affect the Durability of a Lab Diamond?
A.  No. Post-growth Treatment Does Not Reduce Hardness, Strength, or Durability. Treated Lab Diamonds Remain 10 on the Mohs Hardness Scale and Are Suitable for Everyday Wear.