Diamond, Newsletter, Podcast, Press Release

GCAL Lab Process Videos

Diamond Proportion Measurement

Precision optical scanning technology utilizing Helium Polish machines, measures every proportion, angle, facet shape, size, relational angle, and forms the foundation for the diamonds external symmetry and cut grade evaluation

Diamond Weighing

We use precision balances that measure diamonds to the fifth decimal place. Our scales are verified every morning, using master diamonds, and calibrated annually by an ISO 17025 Accredited Calibration Laboratory

Gemprint – Unique Optical Fingerprint of a Diamond

Gemprint, a patented and proven technology, produces a unique optical fingerprint of every diamond, natural or lab grown, and can measure the scintillation of each diamond that is scanned. Here, you will see how Gemprint works, as a low power, visible laser passes through the diamond, refracting and reflecting off each facet, to form a unique light emission pattern that is stored and saved in our global registration database. Gemprint allows for positive identification of a diamond, whether loose or mounted.

Direct Assessment Light Performance

GCAL undertakes great effort to capture actual photos of your diamond, in many different environments and positions, to provide accurate and visual assessments of the diamond. In this video, you are seeing optical brilliance, optical symmetry, hearts, arrows, fire analysis, and photomicrographs.

Color Grading

Here you see a diamond grader moving the stone between master diamonds. All diamonds are graded using precision master stones, which means that each of our master stones, represents the highest possible grade. For example, our E master diamonds represent the highest possible E, so any diamond better than that master (less saturation of color) would be graded a D Color.

Clarity Grading

Here you see a diamond with noticeable inclusions, visible through any angle of the stone. At this stage, the number, size, position, relief, and nature of a diamonds characteristics are assessed, recorded, and photographed.

Diamond 360 Video

In this video, you will see a GCAL technician preparing a diamond for 360 Video. We take great care in thoroughly cleaning the diamond, and providing as magnified a view as possible, in a consistent lighting environment, for easy comparison and contrast when a customer is viewing and choosing between multiple diamonds

Laser Inscription

Here you will see a diamond being inscribed, utilizing the latest cold laser technology, with extremely fine resolution. All laboratory grown diamonds that pass through our lab are inscribed with LAB GROWN or LG, indicating their lab grown origin. Photomicrographs of each laser inscription are recorded for future identification purposes

Raman Spectroscopy

Raman Spectroscopy is an analysis we perform on many diamonds submitted to the lab. This analysis reveals key features of the diamonds atomic composition. In the video, you will see a characteristic raman diamond peak, that all diamonds, lab grown and natural, would have

Diamond View

Very high magnification, combined with very shortwave UV, reveals the diamonds growth structure and pattern, providing a key indicator of how the diamond was formed or grown.


Fluorescence and phosphorescence images of the diamond, reveal key characteristics of the stones growth process

Natural Diamond Verification

Ultraviolet spectroscopy is used for diamond identification and typing

XRF Metal Testing

GCAL utilizes the most sophisticated non-destructive XRF Testing method to determine the elemental composition of each item of jewelry that is submitted to the lab

Metal Engraving

GCAL utilizes a 20 watt fiber laser to engrave all metals and jewelry components