The Laboratory-Grown Diamond Report was GIA's digital-only report for laboratory-grown diamonds, from October 2020 to September 2025. It gave color and clarity grades and stated the growth method, CVD or HPHT.
In more detail
GIA designed it to look distinctly different from its reports for natural diamonds. GIA inscribed each stone with the report number and the word LABORATORY-GROWN. Since 1 October 2025, GIA issues a Laboratory-Grown Diamond Quality Assessment instead. It calls a stone Premium or Standard and gives no D-to-Z or clarity grades.
On a grading report
The report type itself states the origin. IGI marks lab-grown stones with "LG" before the report number, and Comments can note the growth method on request.
Related terms
- Laboratory-grown diamond: A laboratory-grown diamond is a diamond that people grow with machines, by HPHT or CVD. It has essentially the same composition, crystal structure and properties as a natural diamond.
- Natural diamond: A natural diamond is a diamond that formed in the earth, about 160 km deep, under enormous heat and pressure. An eruption carried it to the surface.
- Inscription: An inscription is text that a laser writes on the girdle of a stone, too small to see without magnification. Most often it is the report number.
- HPHT: HPHT stands for high pressure, high temperature. The same conditions can grow a diamond in a laboratory or treat a natural one to change its color.
- CVD: CVD, chemical vapor deposition, is one of the two usual methods for growing diamond in a laboratory. The other is HPHT.
- Diamond grading report: A diamond grading report is an independent lab's record of what a stone is and how it grades. It is true for the day the lab examined the stone.
- Laboratory-Grown Diamond Quality Assessment: GIA's Laboratory-Grown Diamond Quality Assessment rates a lab-grown diamond Premium or Standard. It replaced GIA's D-to-Z lab-grown reports on 1 October 2025.