GIA
Gemological Institute of America
Founded 1931 · Carlsbad, California, USA
GIA developed the 4Cs and the International Diamond Grading System in the 1940s. Both remain the worldwide benchmark for diamond grading.
Official websiteCertifications & Awards
Our diamonds and gemstones are examined and certified by independent gemmological laboratories. Our certification partners include GIA, IGI, HRD Antwerp, Gübelin Gem Lab in Switzerland and the Deutsche Gemmologische Gesellschaft e.V. (German Gemmological Association, DGG). A report describes the stone by cut, colour, clarity and carat — criteria recognised worldwide.
What a certificate proves
The laboratory confirms which stone it examined — and whether it formed naturally or was grown in a laboratory.
Cut, colour, clarity and carat weight are assessed against a single system, which makes stones comparable.
A report records whether a stone has been treated — for example by heating, filling or irradiation.
The report is issued by a laboratory that neither sells the stone nor profits from its sale.
Our certification partners
We work with laboratories whose reports are recognised internationally. Which institute examines a stone depends on its type, origin and value.
GIA
Founded 1931 · Carlsbad, California, USA
GIA developed the 4Cs and the International Diamond Grading System in the 1940s. Both remain the worldwide benchmark for diamond grading.
Official websiteIGI
Founded 1975 · Antwerp, Belgium — laboratories worldwide
IGI grades diamonds, gemstones and finished jewellery and is one of the largest independent laboratories in the world.
Official websiteHRD
Founded 1973 · Antwerp, Belgium
The Belgian institute issues reports for natural diamonds, laboratory-grown diamonds and jewellery — from the centre of the diamond trade.
Official websiteGübelin
Founded 1923 · Lucerne, Switzerland
The Swiss laboratory is particularly known for examining coloured gemstones, including origin determination and treatment detection.
Official websiteDGG
Founded 1932 · Idar-Oberstein, Germany
The German Gemmological Association is one of the three oldest gemmological institutes in the world and combines education with the examination of gemstones and diamonds.
Official websiteFounding, headquarters and focus are taken from the institutes themselves; reviewed October 2026.
At Masry Gems
For our certified stones we will confirm the examining laboratory, report number and grading on request — before you order. If you want certainty about a stone’s properties before buying, the grading report is the right starting point.
Frequently asked questions
A diamond certificate is an independent report on a polished diamond. It confirms the stone's identity and grades the 4Cs: cut, colour, clarity and carat weight. It is issued by a gemmological laboratory that neither sells the diamond nor profits from its sale.
Our diamonds and gemstones are examined by laboratories including GIA, IGI, HRD Antwerp, Gübelin Gem Lab and the Deutsche Gemmologische Gesellschaft e.V. (German Gemmological Association, DGG). The report for a particular stone names the laboratory that examined it.
Both institutes are independent and internationally recognised. GIA is the benchmark because it developed the 4Cs and the International Diamond Grading System; IGI is also a large, established laboratory. What matters is that the report matches the specific stone and that its findings can be verified.
For our certified stones we will confirm the laboratory, report number and grading before you buy, so you can check the report first. Simply ask us about the specific piece.
Yes. Laboratory-grown diamonds receive their own reports, which clearly distinguish them from natural diamonds — for example as a Laboratory-Grown Diamond Report from HRD Antwerp or IGI.
A report makes comparable what the eye cannot see — colour, clarity or a treatment, for instance. It protects you from buying on impression alone, and it helps later with insurance or resale.
Every stone in our collection is selected by hand. The accompanying grading reports make its quality traceable.