This article has been updated as of August 29, 2025.
Original publish date: June 1, 2022
Have you heard of GCAL 8X® Ultimate Cut Grade Lab-Grown Diamonds? These exceptional lab-grown diamonds achieve excellent grades in all eight aspects of cut quality — the highest standard possible in precision diamond cutting. By guiding your customers toward GCAL 8X, you can confidently offer them unmatched brilliance, fire, and sparkle with every purchase.
GCAL (the Gem Certification & Assurance Lab) developed the 8X cut grade standard to distinguish the best of the best diamonds. Only extraordinarily brilliant and beautiful diamonds achieve an excellent grade in all eight aspects of cut quality assessment.
8X® Diamond Grading Factors
Factor | Grade |
|---|---|
1. Polish | EXCELLENT |
2. External Symmetry | EXCELLENT |
3. Proportions | EXCELLENT |
4. Optical Brilliance | EXCELLENT |
5. Fire | EXCELLENT |
6. Scintillation | EXCELLENT |
7. Optical Symmetry | EXCELLENT |
8. Hearts & Arrows/Shape Aesthetics | EXCELLENT |
Why Choose 8X Lab-Grown Diamonds?
There are eight perfect reasons to choose 8X lab-grown diamonds. The first three of the 8X grading factors analyze physical precision — the exactness of the physical surface, the facet shapes, as well as the angles.
#1 Polish — Skill and time are required to produce a well-polished lab-grown diamond. GCAL gemologists examine every facet to ensure it is free of polish marks, burns and scratches.
#2 External Symmetry — Master cutters identically shape each facet around the diamond and ensure they are perfectly aligned. Only diamonds with precision faceting achieve a GCAL excellent grade.
#3 Proportions — Optical scanning technology measures each facet and angle to produce an accurate, to-scale diagram of every diamond.
The next three of the 8X grading factors analyze the light-handling ability of a diamond. The combination of these factors is the essence of what makes any lab-grown diamond visibly shine, dance, and sparkle from across a room.
#4 Optical Brilliance is the overall return of white light to the viewer. It is measured to the thousandth decimal place. White areas indicate light return/brilliance, while dark blue areas indicate light loss.
#5 Fire results when white light travels through a diamond and is dispersed into its rainbow of spectral colors. These flashes of color contribute to sparkle and are best viewed as the diamond moves. Each 8X lab-grown diamond certificate has a video demonstrating its fire.
#6 Scintillation refers to the flashes of white light, or sparkle, produced when light is reflected from a diamond as it moves. Each 8X lab-grown diamond certificate has a scintillation video demonstrating the light returned from a single beam of light when the stone is rotated.
The last two 8X grading factors scrutinize the optical precision — the craftsmanship and the precise alignment of the crown and pavilion facets in harmony to achieve aesthetic perfection.
#7 Optical Symmetry is visualized in a photograph of the lab-grown diamond taken in a specific-colored lighting environment. The evenness of the pattern illustrates the precision and uniformity of facet shapes and alignment.
#8a Hearts & Arrows — Precision faceting for round lab-grown diamonds is visualized as Hearts & Arrows. Each pattern is the result of superior facet placement and exact alignment.
#8b Shape Aesthetics — Analyzes features including axis length and axis width which are unique to Oval, Square, Marquise, Pear, and Radiant lab-grown diamonds.
Each 8X lab-grown diamond comes with an interactive GCAL grading certificate that includes a dazzling 360-degree video, fire video, scintillation video, Gemprint® fingerprint image, photomicrographs, to-scale proportion diagram, and laser inscription.
Introducing Radiant Cut — the Newest Addition to Stuller’s GCAL 8X Lineup
Radiant lab-grown diamonds are celebrated for blending the geometric elegance of emerald cuts and the sparkle of brilliant cuts. This new 8X lab-grown diamond shape joins our thoughtfully curated selection of popular shapes: Round, Oval, Square, Marquise, and Pear.
There is rising demand for custom, unique pieces, and radiant shapes fit perfectly into this narrative with their bold, modern silhouette. In fact, elongated stone shapes such as radiant, oval, and marquise are becoming top choices for engagement ring center stones. Read more about the latest trends influencing engagement rings and wedding bands in 2025 here.
GCAL 8X — Brilliance Beyond Compare
In a market where customers seek both beauty and assurance, GCAL 8X® Ultimate Cut Grade Lab-Grown Diamonds deliver on every promise. From flawless polish to unrivaled light performance, each lab-grown diamond represents the pinnacle of precision cutting and the artistry of modern gem craftsmanship. Backed by GCAL’s trusted certification and enhanced with interactive visuals, you can present every 8X lab-grown diamond with complete confidence.
Whether your customer desires a timeless round, an elegant oval, or the bold new radiant shape, Stuller’s expanded 8X lab-grown diamond assortment ensures that you can meet their vision with unmatched brilliance, fire, and scintillation. Elevate your sales, inspire trust, and offer a lab-grown diamond that truly stands apart — because nothing compares to the perfection of eight perfect scores.
