The certificate: what every diamonds in glass® piece documents

Diamond Education

The certificate: what every diamonds in glass® piece documents

Every diamonds in glass® piece is delivered with a certificate. It names model, serial number, carat of the diamond, gold and laboratory certificate. Diamonds from 0.30 carat are certified by GIA, below that the house issues its own certificate, pavé diamonds are certified by HRD.

diamonds in glass®·5 min read·12 October 2026

A diamond in glass is an object that raises questions. The first is often: is it real? The answer comes with every piece, on a certificate that documents more than just the stone.

What the certificate states

  • Collection and model, with name and number.
  • The serial number of the individual piece.
  • The diamond in the glass sphere with its carat weight; with pavé, also the total weight of the stones.
  • The gold with carat and colour, or platinum.
  • The laboratory certificate belonging to the stone.
  • The note that the glass sphere was made by hand in Austria.
  • The date of issue.

GIA, HRD or the house certificate

Which laboratory certificate applies depends on the stone. Diamonds from 0.30 carat are certified by the Gemological Institute of America, GIA for short. For diamonds below 0.30 carat, diamonds in glass® issues its own certificate. The small pavé diamonds that set the hook, halo or line of some pieces are certified by HRD Antwerp.

StoneCertificate
Diamond in the sphere from 0.30 caratGIA
Diamond in the sphere below 0.30 caratCertificate of diamonds in glass®
Pavé diamonds in the settingHRD Antwerp

The serial number: one piece, one number

The serial number is created with the order and accompanies the piece through production. It links the certificate to exactly this piece and makes it distinguishable, even when two pieces are the same model.

Why the origin of the sphere is noted

What makes a diamond in glass special is the sphere itself. It is made by hand in Austria, in a process patented worldwide. That is why the certificate names not only the stone and the gold, but also the origin of the glass sphere.

The essentials

  • Every piece is delivered with a certificate.
  • From 0.30 carat GIA certifies, below that the house itself.
  • Pavé diamonds are certified by HRD Antwerp.
  • The serial number links certificate and piece.

We answer questions about stone and certificate in a personal conversation.

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Frequently asked questions

Answered briefly

  • Yes. Every diamonds in glass® piece is delivered with a certificate naming model, serial number, diamond, gold and laboratory certificate.

  • GIA laboratory certificates are common for larger stones. For diamonds below 0.30 carat, diamonds in glass® issues its own certificate; from 0.30 carat GIA certifies.

  • HRD Antwerp is a diamond laboratory in Antwerp. It certifies the small pavé diamonds that set the setting of some pieces.

  • It documents that the glass sphere was made by hand in Austria, in the diamonds in glass® process patented worldwide.

diamonds in glass®

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