FGA Gem Trading and Testing Laboratory

31/01/2026

Some gifts sparkle long after they're given.

Back in 1955, Diamond Corporation, Limited—led by Sir Ernest Oppenheimer—donated more than 1,500 carats of diamonds to GIA. Known as the Sir Oppenheimer Student Collection, the gift included an incredible variety of crystal shapes, sizes and qualities, many of which were cut specifically for students to study.

The donation was made in recognition of GIA’s growing role in the diamond trade, and it helped the Institute expand its diamond evaluation courses and strengthen hands-on grading training. Decades later, this collection is still shaping the next generation of gemologists.

Learn more about GIA’s diamond research on our website: https://bit.ly/4jLh62l

Photo courtesy of the Sir Oppenheimer Student Collection

08/01/2026

All eyes on this 11.23-carat pezzottaite—literally! This rare pink beryl-group mineral, first discovered in Madagascar in 2002, displays multiple cat’s-eye effects, a phenomenon almost never seen. Gemologists at GIA’s laboratory in Tokyo discovered that iridescent, bent growth tubes within the gem are responsible for the numerous glowing cat’s eyes that make this pezzottaite a truly captivating natural wonder.

Learn more about this gem in a recent issue of G&G on our website: https://bit.ly/45l2jVK

Photomicrograph field of view 4.80 mm

31/12/2025

AVDEEVITE from Kat Chal (Palelni) Momeik, Myanmar…

Look at this rare mineral from Myanmar 🔍

Avdeevite is a member of the beryl group and was identified relatively recently from a granitic pegmatite at the Kat Chay (Palelni) mine in Momeik, Myanmar.

Crystallising in the hexagonal system, avdeevite forms pink, vitreous, translucent-to-transparent crystals with a Mohs hardness of 8. In January 2025, the Gem Testing Laboratory at the Gem and Jewelry Institute of Thailand (GIT) received for identification a 0.53 g rough pink specimen, shaped like a folding fan or a sheaf-like aggregate (pictured). The sample was said to originate from Myanmar.

Small quantities of polished avdeevite could enter the gem market in the future. However, due to its rarity and limited occurrence, it will most likely remain a collector’s stone.

📸 0.53 g avdeevite specimen by P. Panpum.

Gem-A Members can read more in The Journal of Gemmology (Volume 39, No. 7): https://gem-a.com/publications/the-journal-of-gemmology/

Become a Gem-A Member to access our renowned publications: https://gem-a.com/membership/

20/12/2025

💎 Gemology Class43: Sphene (Titanite)
Sphene, also known as Titanite, is one of the most fascinating gemstones in the world of gemology, famous for its exceptionally high fire and brilliance — even higher than diamond.
🔹 Chemical Composition: Calcium Titanium Silicate (CaTiSiO₅)
🔹 Hardness: 5 – 5.5 (Mohs)
🔹 Crystal System: Monoclinic
🔹 Refractive Index: 1.885 – 2.050
🔹 Dispersion: 0.051 (higher than diamond)
🔹 Optic Character: Biaxial (+)
✨ Why Sphene is Special?
Sphene shows very strong dispersion, producing intense rainbow flashes. It also has high birefringence, which causes noticeable double images when viewed through a loupe — a key identification feature.
🎨 Color Range:
Yellow, yellow-green, green, brown, and rare orange tones. Strong pleochroism allows different colors to be seen from different angles.
✂️ Cut & Use:
Usually cut in brilliant or modified cuts to maximize fire. Due to its softness and perfect cleavage, sphene is mainly used in pendants or collector stones, not daily-wear rings.
🌍 Major Sources:
Pakistan, Afghanistan, Madagascar, Sri Lanka, Brazil, and Austria.
🧼 Care & Handling:
Sphene is delicate. Avoid heat, chemicals, ultrasonic, and steam cleaners. Clean gently with mild soap and water.
📌 Gemology Tip:
If a gemstone shows extraordinary fire, strong pleochroism, and visible double refraction, it could be sphene.
💠 Conclusion:
Sphene is a rare beauty — not valued for durability, but admired for its unmatched brilliance and optical charm. A true gem for collectors and gemology students.

16/12/2025

11/12/2025

Starting January 1, 2026, GIA will launch redesigned colored stone reports and expanded services. These updates build on GIA's extensive research sample collection and more than 75 years of colored stone reporting expertise.

Key updates include:

- Elevated design for enhanced storytelling

- Highlights the most relevant gemological information, making it easier to understand each gem's unique story

- Expanded origin-determination services to include opal, peridot and demantoid garnet—joining our existing country-of-origin determination services

- Revised weight categories and related fees for colored stone submissions

Learn more: https://bit.ly/44hUf82

04/12/2025

04/12/2025

04/12/2025

04/12/2025