In diamond manufacturing terminology, small loose diamonds used in halos, channel bands, micro-pavé, and Swiss watch bezels are categorized by weight into two distinct industry classes:
Because weighing thousands of individual 0.01-carat stones is commercially impossible, the wholesale diamond trade sorts and trades melee exclusively using standardized sieve plates.
A diamond sieve set consists of a nesting stack of circular brass or stainless-steel plates, each perforated with hundreds of laser-cut circular apertures. Sieve numbers are designated with plus (+) and minus (-) symbols:
| Sieve Size | Diameter Range (mm) | Approx. Carats per Stone | Stones per Carat (SPC) |
|---|---|---|---|
| -000 | 0.80 – 0.90 mm | 0.003 – 0.004 ct | 250 – 300 SPC |
| 000 to 00 | 0.90 – 1.05 mm | 0.005 ct | 200 SPC |
| +0 to +1 | 1.10 – 1.20 mm | 0.007 ct | 140 – 150 SPC |
| +2 to +3 | 1.30 – 1.40 mm | 0.010 ct (1 point) | 100 SPC |
| +4 to +5 | 1.50 – 1.60 mm | 0.015 ct (1.5 pts) | 65 – 70 SPC |
| +6 to +6.5 | 1.70 – 1.85 mm | 0.020 – 0.025 ct | 40 – 50 SPC |
| +8 to +8.5 | 2.00 – 2.15 mm | 0.035 – 0.040 ct | 25 – 30 SPC |
| +10 to +11 | 2.40 – 2.50 mm | 0.055 – 0.060 ct | 16 – 18 SPC |
| +13 to +14 | 2.90 – 3.10 mm | 0.10 ct (10 points) | 10 SPC |
In micro-pavé setting, a master setter drills tiny conical seats into gold or platinum, placing dozens of melee diamonds side-by-side held only by microscopic bead prongs raised from the base metal. If diamond diameters vary by even 0.05 mm, severe manufacturing defects occur:
Lavish calibrated melee parcels undergo secondary digital optical gauge sorting, guaranteeing dimensional consistency to within +/- 0.025 mm.
Unlike large certified solitaires which come with individual IGI certificates, melee parcels are ordered and certified by the batch. At Lavish, our calibrated parcels are categorized into standardized wholesale quality tiers:
The premier choice for luxury Swiss watchmakers and high-jewelry maisons. 100% colorless, flawless face-up scintillation, and zero strain.
The workhorse tier for bridal engagement halos and fashion eternity rings. Beautiful, bright white appearance delivering optimal gross margins.
In jewelry benchwork and wholesale mounting, millimeters matter far more than carat weight. A setting is engineered to accommodate physical millimeter tolerances, not carats. Here is the definitive carat-to-mm conversion reference across all major diamond cuts.
Diamond shape defines the architectural silhouette, facet geometry, and personal aesthetic of a gemstone. From the classic 57-facet Round Brilliant to the geometric step cuts of Emerald and Asscher, explore the technical specifications and ideal ratios of all 12 major diamond cuts.
Navigating the global wholesale diamond market requires understanding commercial trade structures, pricing mechanics, and logistics. From single certified solitaires to high-volume calibrated parcel orders, here is how retail jewelers, private designers, and manufacturing houses maximize margin and supply security.