Professional Gem Sciences Laboratory

10/20/2026

💎 This Diamond Glows in the Dark! | Rare Phosphorescence Explained

In this video, we take you behind the scenes at PGS Laboratory to demonstrate an extraordinarily rare phenomenon: diamond phosphorescence.

Unlike fluorescence, phosphorescence occurs when a diamond continues to glow even after the ultraviolet (UV) light source has been removed.

Further gemological testing revealed that this particular diamond was laboratory-grown.

🔬 Watch as we explore this fascinating optical phenomenon and demonstrate how scientific observation and routine gemological testing help identify diamonds and determine their origin.

Learn more about our laboratory services and gemology courses at www.pgslaboratory.com.

10/14/2026

Ever wonder how gemologists figure out what kind of gemstone they're looking at?

Come behind the scenes at PGS Laboratory as we perform a Specific Gravity (SG) test on a client's mystery gemstone!

Using a precision scale, some water, and a little math, we can measure a gemstone's density and uncover valuable clues about its identity.

🎥 Watch our latest video to see how it's done!

Have a mystery gemstone of your own? We'd love to hear about it in the comments!

10/02/2026

A day in the lab - a multi row natural diamond bracelet 🔬

08/22/2026

Advance your gemology skills with Professional Gem Sciences Laboratory. Learn to evaluate loose and finished jewelry. We now have 2 options either in person or on your own schedule with our new online diamond and colored stone courses. Enroll today with PGS!Professional Gem Sciences Laboratory
Eitan Tashey Myriam Tashey The Jewelers Center

08/19/2026

A beautiful pair of jade 💚 earrings recently came through the laboratory. But with jade, appearance alone doesn’t tell the whole story.

Our examination identified the material as natural jadeite jade, A-Jade, meaning we found no evidence of dyeing, bleaching, or polymer/resin impregnation 🚫.

That distinction is an important one. Jadeite is commonly treated to improve its color or transparency, and those treatments can have implications for durability, stability and value. With A-Jade, the color, texture and translucency you see are properties of the natural stone itself.

For collectors, jewelers and consumers, this is exactly where independent gemological testing matters 🔬: not simply identifying what a gemstone is, but determining what has - or has not - been done to it.

08/17/2026

This Week in the Lab: Garnet Inclusions, Imitation Emerald Triplets, Diamond Scratch Testing, & more…

View our recent newsletter and upcoming gemology courses:

https://mailchi.mp/2eac5a548016/pgsl-this-week-in-the-lab-summer2026courses

Diamond Grading & Identification: August 30 - September 2
Gemstone Grading & Identification: September 13 - September 16

PGS Laboratory will be offering in-person gemological classes and hands-on training this August and September. Space is limited, and early registration is strongly encouraged. These classes give students the opportunity to work directly with seasoned gemologists and examine carefully selected diamon...

07/17/2026

Join us on August 5th as we welcome industry expert Shelly Sergent to the Jeweler's Center

07/14/2026

Three pear-shaped diamonds walk into a lab… and none of them agree on proportions. 💎

Which length-to-width ratio looks best to you?

1:1.25 — short and bold
1:1.60 — classic and balanced
1:2.10 — long and dramatic

Many in the trade lean toward 1:1.50–1.60, but beauty is in the eye of the beholder.

Watch the video and cast your vote in the comments: 1.25, 1.60, or 2.10?

How does a diamond’s length-to-width ratio influence its overall ap...

03/25/2026

🔹swipe to see a cubic inclusion🔹 Today in the Lab: This 3-stone ring has a brilliant green Colombian natural emerald beryl with two natural diamond side stones - one which features a cube-shaped inclusion, a rare and opaque cuboid naturally formed through fibrous growth in the stone.

02/15/2026

This Tuesday, Jennifer Heebner, fresh from her Tucson travels, had the privilege of updating the Chicago jewelry community on the latest trends and insights. The Jewelers Center Professional Gem Sciences Laboratory Myriam Tashey

PGS had the pleasure of welcoming jewelry journalist Jennifer Heebner to Chicago this past week, following her trip to the Tucson Gem Show. Jewelers and enthusiasts alike gathered for her talk at the Maller's Building to learn about upcoming trends for 2026. Heebner has been covering the jewelry ind...