Lesson 16 · Diamonds & Engagement Rings · 34 seconds
From a diamond seed to a finished stone
In CVD growth, carbon from a gas builds onto a diamond seed inside a chamber; HPHT is a different method using high pressure and high temperature. Either way, the rough still needs cutting and polishing before it becomes a finished gemstone.
What this lesson shows
Two growth methods, then skilled finishing.
Simplified schematics show CVD, where carbon from a gas builds onto a diamond seed inside a chamber, and HPHT, a different method that uses high pressure and high temperature. The rough is then cut and polished. Drawings are not to scale.
Three quick takeaways
What to actually do when you shop
- CVD builds carbon from a gas onto a diamond seed inside a chamber.
- HPHT is a different method that uses high pressure and high temperature. Either way, the rough still needs cutting and polishing.
- Seed, growth, skilled finishing: growth is only part of a lab-grown diamond's story.
The seed, rough and diamond footage is AI-generated illustration. The CVD and HPHT drawings are simplified schematics, not equipment diagrams or yield comparisons. The narration uses an AI-generated voice. Captions are shown in the video.
Read the transcript
This tiny diamond can help grow a lab-grown diamond. In CVD growth, carbon from a gas builds onto a diamond seed inside a chamber. HPHT is a different method, using high pressure and high temperature. Either way, growth is only part of the story. The rough still needs cutting and polishing before it becomes a finished gemstone. Seed, growth, skilled finishing. Explore more in the Aydins Jewelry Learning Center.
Sources
- GIA Gems & Gemology, Summer 2024: update on laboratory-grown diamonds: www.gia.edu/gems-gemology/summer-2024-gia-update-on-laboratory-grown-diamonds
- GIA, HPHT and CVD diamond growth processes: www.gia.edu/hpht-and-cvd-diamond-growth-processes
- Federal Trade Commission, In the Loupe: advertising diamonds, gemstones and pearls: www.ftc.gov/business-guidance/resources/loupe-advertising-diamond-gemstones-pearls
Related lessons
Lab-grown diamond vs cubic zirconia · lab-grown diamond is diamond.
Why lab-grown diamonds can cost less · the supply story behind the price.
What a diamond tester actually proves · why a beep does not reveal origin.
Next step
Explore lab-grown diamond jewelry.
Compare the specifications on each piece.