Medium
Bi-fold Report
21 × 14.7 cm
- Bi-fold Report
- Full Identification
- Treatment Analysis
- Origin Determination
- Photo of Item
Since 2019 — Antwerp, Belgium
Trusted Expertise in
Gemstone Reports
International gemological laboratory providing comprehensive analysis and reports for diamonds, colored gemstones, pearls, and jewelry.
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Discover ALGT's commitment to excellence
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Enter Virtual TourAbout ALGT
Setting the standard in independent gemstone reports since 2019
The Antwerp Laboratory for Gemstone Testing (ALGT) is an independent gemological laboratory headquartered in the heart of Antwerp — the world's diamond capital. Founded in 2019, ALGT has built a reputation for precision, integrity, and innovation.
Our laboratory employs advanced spectroscopic techniques combined with classical gemological methods to deliver accurate and reliable reports for dealers, auction houses, jewelers, and private clients worldwide.
In addition to Antwerp, we operate a fully-equipped facility in Shanghai, China, serving the vibrant Asian gemstone market.
7+
Years
150K+
Reports
2
Laboratories
Why Choose ALGT
Tradition meets cutting-edge technology
🔬
Advanced Equipment
State-of-the-art gemological instruments for precise analysis
🎓
Expert Gemologists
Team of internationally certified gemological professionals
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Global Recognition
Reports accepted and trusted by dealers worldwide
⚡
Fast Turnaround
Efficient processing with rapid report delivery options
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Confidential & Secure
Your gemstones handled with utmost care and discretion
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Comprehensive Reports
Detailed analysis covering all critical gemstone parameters
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Personalized Service
Dedicated support tailored to your specific needs
Our Equipment
State-of-the-art instruments powering our analysis
Renishaw inVia™ Confocal Micro-Raman Microscope
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LIBS — Laser Induced Breakdown Spectroscopy
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EDXRF QUANT'X Spectrometer
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FTIR — Fourier-Transform Infrared Spectroscopy
UV-Vis-NIR Spectroscopy
DiamondView™
DTC Melee Sorting Machine
J-SCREEN Diamond Screener
Our History
A journey of growth and dedication to excellence
2019 Antwerp
ALGT Established in Antwerp
2021 Antwerp
Team Grew to Nine Members
2023 Shanghai
ALGT Shanghai Launched
2024 Shanghai
CMA Accreditation in Shanghai
2024 Shanghai
Shanghai Lab Relocated to Ocean Building
2025 Antwerp
Micro-Raman Spectrometer Acquired
2026 Shanghai
Consumer Rights Day in Shanghai
Our Team
Internationally certified gemologists
Mingyue Yang
Director & Chief Gemmologist
Co-founder of ALGT. Senior gemmologist with expertise in gemstone testing, laboratory operations, and gemmological research, including pearl-related publications.
Segers Marc
General Manager & Chief Gemmologist
Co-founder of ALGT. Over 30 years of experience in gemology. FEEG diploma holder and recipient of the KIEA Gold Medal for diamond expertise from the King of Belgium.
SS
Sijie Sun, GG
Operations Manager
Graduate Gemologist (GG) and ALGT founding-team member, currently overseeing the daily administrative operations of the Shanghai laboratory.
Our Services
Comprehensive gemological services for trade and private clients
Large
Tri-fold A4 Report
29.5 × 21 cm
- Tri-fold Report
- Full Identification
- Treatment Analysis
- Origin Determination
- Detailed Photo
- Two Spectrum Data Charts
Luxury
Hardcover Two-fold Folder
36 × 27 cm
- Full Identification
- Treatment Analysis
- Origin Determination
- Detailed Photo
- Two Spectrum Data Charts
- Additional Information Sheet
BEST
Premium
Hardcover Prestige Booklet
60 × 27 cm
- Elegant Blue Hardcover (4–5 pages)
- Stunning High-Resolution Photography
- Detailed Inclusion Imagery
- Insightful Description of the Item
- Origin Introduction
- Bespoke for High-Value Pieces
Service Price List 2025
In Euro, Excl. 21% VAT
Natural Diamond Report (loose)
| Carat Weight | Fee (€) |
|---|---|
| ≤0.29 | 32 |
| 0.30-0.49 | 37 |
| 0.50-0.99 | 42 |
| 1.00 + | 45/ct |
Rough Diamond Identification Report
| Carat Weight | Fee (€) |
|---|---|
| ≤0.99 | 30 |
| 1.00 + | 30/ct |
| Yield Calculation ≤0.99 | 40 |
| Yield Calculation 1.00 + | 40/ct |
Laboratory-Grown Diamond Report (loose)
| Carat Weight | Fee (€) |
|---|---|
| Any weight | 25 |
* ALGT reserves the right to change these prices at any time. Discounts may be applicable for large volumes.
News & Library
Latest from ALGT and the gemological world
EventsALGT Shares Gemstone Testing Expertise with Belgian Jewelry Professionals
This Monday, ALGT’s General Manager and Chief Gemologist, Marc Segers, was invited by Sofie Vanheukelom, President of Studio Goudmijn, to give a lecture at Kasteel van Bokrijk in Belgium…
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IdentificationWhen a 30 ct “Emerald” Turns Out to Be Green Beryl: ALGT’s Gemological Analysis
Recently, ALGT received a bluish green gemstone weighing over 30 ct. The client submitted the stone as an emerald; however, after examination, the Antwerp Laboratory for Gemstone Testing reached a different conclusion…
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IdentificationWhy Not Every Pink-Orange Sapphire Can Be Called Padparadscha
In today’s jewellery market, the naming of many stones as “Padparadscha” is problematic — or, to put it more mildly, does not comply with the internationally accepted grading standards for Padparadscha sapphires…
Read more
Contact Us
Get in touch with our team
🇧🇪 HEADQUARTERS
ALGT Antwerp
🇨🇳 ASIA OFFICE
ALGT Shanghai
📍Room 1201, Ocean Building, 550 East Yan'an Road, Huangpu District, Shanghai
📞(021) 60704858
💬WeChat: ALGTSHANGHAI
🕐Mon–Fri: 9:00 – 18:00 (CST)
Proud member of
International Colored Gemstone Association
CMA
China Inspection Body and Laboratory Mandatory Approval