A production line can't stop to re-cut a seat because one diamond in the parcel runs large. Guru Diam supplies calibrated diamonds to jewelry manufacturers, cut to exact millimeter sizes so they drop into cast settings without adjustment, in lab-grown and natural.
What calibrated means for production
A calibrated diamond is cut to a set size rather than to save weight, so every piece in a parcel fits the same seat. Our melee is matched to within 0.05 to 0.10 mm, and matched pairs within 0.1 to 0.2 mm and about one color grade. That lets your setters work from the CAD without sorting parcels by hand. The calibrated melee guide lists typical tolerances for pavé, tennis and eternity mountings.
Calibrated rounds, fancy shapes and layouts
We supply calibrated rounds from under 1 mm upward, plus calibrated fancy shapes for side diamonds, line bracelets and cluster work. Browse round melee and pointers, fancy loose layouts and matched pairs, or read about matched fancy-shape side diamonds. If a size or shape isn't in stock, we source or cut it to your specification.
Parcels and pricing for manufacturers
Calibrated diamonds are sold in parcels by size and grade, and there is no minimum order, so you can buy one production run at a time. Our diamond parcel guide explains how parcels are graded and priced. Current per-carat trade ranges by mm band are in our Lab-Grown Diamond Price Index. Our lab-grown melee is CVD Type IIa.
Inventory feed and repeat orders
Manufacturers who reorder the same sizes can connect our inventory to their own system through an API or CSV feed, so stock levels show up where your buyers plan production. Each account has a dedicated account manager who handles repeat parcels.
How manufacturers order
Open a trade account; applications sent before 4 PM ET are approved the same business day. Orders placed before 6 PM ET ship the same day from New York, and international orders arrive in 3 to 4 business days. We take wire, ACH, checks and debit cards, and established accounts can get credit terms. If you also need finished pieces, our wholesale jewelry and custom manufacturing run in-house in New York and India.
Why manufacturers source calibrated diamonds from Guru Diam
We supply more than 3,000 trade accounts, keep lab-grown and natural parcels under one account, and are a JBT member. Stock items carry a 14-day free return.
For mm-to-carat charts, sieve sizes and grades, see our complete guide to melee diamonds.
Open a trade account · WhatsApp +1 (929) 340-3449
Frequently asked questions
What are calibrated diamonds?
Calibrated diamonds are cut to a set millimeter size so every diamond in a parcel fits the same setting without adjustment.
How tight is your calibration?
Melee is matched to within 0.05 to 0.10 mm. Matched pairs are within 0.1 to 0.2 mm and about one color grade.
Do you have a minimum order for calibrated parcels?
No. There is no minimum order quantity.
Can we connect your inventory to our system?
Yes. Trade partners can use our API or CSV feed.
Can you cut a size you don't stock?
Yes. We source or cut diamonds to your specification.
