Understanding Lab Diamond Quality
Lab diamonds are graded by the same 4Cs as mined diamonds, but color and clarity distributions differ from mined stones. Lab diamonds tend to have higher clarity and more consistent color, making quality selection somewhat different. Understanding these grades helps retailers stock the right quality at each price point.
Color Grades: D-F vs G-H
D-F (Colorless): No visible color, even to trained gemologists. The highest color grade. D-F lab diamonds look bright white in any setting and are ideal for engagement rings and premium jewelry. D-F is the most common grade in lab diamonds (easier to achieve colorless in a lab than in nature).
G-H (Near-Colorless): Very slight warmth, invisible to most people once set in jewelry. G-H offers excellent value — looks colorless in normal viewing while costing less than D-F. For white gold/platinum settings, G-H appears colorless. For yellow gold, the warmth is masked by the metal.
I-J and below: Visible warmth, may appear slightly yellow. Budget option, best in yellow gold settings. Less common in lab diamonds (most producers target D-H).
Clarity Grades: VVS vs SI
VVS (Very Very Slightly Included): Minute inclusions, extremely difficult to see under 10x magnification. Eye-clean to all viewers. Premium clarity grade.
VS (Very Slightly Included): Minor inclusions, difficult to see under 10x. Eye-clean in almost all cases. Excellent value — most customers can't distinguish VS from VVS with the naked eye.
SI (Slightly Included): Inclusions visible under 10x, may be visible to the naked eye in larger stones (1.5ct+). Budget-friendly. SI1 is often eye-clean; SI2 may show visible inclusions.
Lab diamonds tend to have higher clarity than mined diamonds — VVS-VS is standard, and SI is less common.
"Eye-Clean" Is What Matters
For most customers, "eye-clean" (no visible inclusions without magnification) is the practical standard. VS clarity is almost always eye-clean. SI1 is often eye-clean (especially in brilliant cuts that mask inclusions). VVS offers guaranteed eye-clean but at a premium. For jewelry, don't overpay for VVS if VS looks identical to the naked eye — the savings can go toward a larger stone.
Cut Style and Clarity Visibility
Brilliant cuts (round, cushion, oval) mask inclusions with their sparkle — SI can look eye-clean. Step cuts (emerald, asscher) show inclusions more readily (large, open facets) — choose VVS-VS for emerald cuts. The setting also matters: bezels and halos hide inclusions at the edges; prong settings show more of the stone.
Quality by Price Point
Premium ($2,000+ retail): D-F color, VVS clarity, excellent cut. For customers who want the best.
Mid-range ($800-2,000): D-F or G-H color, VS clarity, very good/excellent cut. Best value — looks identical to premium to most viewers.
Value ($300-800): G-H color, VS-SI clarity, very good cut. Affordable, still beautiful.
Most lab diamond jewelry falls in the mid-range — D-F/VS is the sweet spot for quality and value.
Certification and Consistency
Always rely on IGI/GIA certification for color/clarity grades — don't trust seller claims without independent verification. Lab diamond grading is consistent, but certificates provide proof. Holycome's lab diamonds are IGI/GIA certified with documented color and clarity grades.
Inventory Strategy
Core inventory: D-F color, VS clarity (best value, 50% of stock). Premium: D-F, VVS (25%). Value: G-H, VS-SI (25%). For emerald/asscher cuts: upgrade to VVS. For round/cushion/oval: VS is sufficient. This tiered approach covers all price points while maintaining quality.
Shop quality-graded lab diamonds — IGI/GIA certified, factory direct.