Our diamond screening practices are designed to ensure that the diamonds we sell are exactly what our customers ordered.

Processes we have in place and the housing of an on-site GIA screening lab help us guarantee the integrity of every diamond sold. 

The screening process for all loose diamonds starts as soon as it arrives into our facilities. At that point, they are separated by size to determine the appropriate screening method. 

To screen all colorless and near colorless diamonds .94 millimeters and smaller we utilize the DIATRUE.

Nearly all round diamonds between .95 millimeters to 3.9 millimeters, go to the GIA Melee Analysis lab within Stuller while Fancy shapes in these sizes are screened by Stuller using the ASM2.

And for diamonds 3.9 millimeters and larger, we use the GIA ID 100 and DIATRUE.

Referrals from all screening stations are redirected to Stuller Gem Lab and tested using advanced instruments, including Raman, FTIR, UV Visible Near InfraRed, and fluorescence spectrometers, for proper identification.

The increase in popularity of Lab-Grown Diamonds in recent years, has led to added screening measures.

To maintain the integrity you’ve come to expect, Stuller houses lab-grown diamonds in a separate vault from natural diamonds.

Lab-Grown and natural diamonds are always kept separate when flowing through our facilities. Throughout the stone-setting process, lab-grown diamonds are kept in blue sleeves to ensure lab-grown and natural diamonds are never mixed.

When you receive loose diamonds from Stuller, the packaging it’s delivered in will help you easily distinguish what is natural and what is lab grown.

For natural melee, you’ll receive either a white or gray parcel. The white parcel indicates that the diamonds inside were screened by the Stuller lab, whereas the gray parcel indicates the diamonds were screened through the GIA Melee Analysis and are sealed with a GIA sticker.

Lab-grown melee will arrive in a blue parcel. And Lab-Grown diamonds weighing a third of a carat and larger have ‘Lab-Grown’ inscribed on the girdle and are packaged with an assurance card stating that they have been screened by the Stuller lab for peace of mind.

Stuller screens all diamonds submitted to our CAD/CAM department. We utilize advanced equipment to confirm your diamonds origin, prior to setting. Once stone setting processes are complete, we perform one final screen to ensure the diamonds you submitted were set in your design. 

Stuller also extends its high standards and expectations to all jewelry vendors. We screen every piece of diamond set jewelry when it is received at our facility.