Quality & Certificates

Every ONGEMS gold piece comes with a certificate of authenticity. It confirms that the jewellery was made by our brand and records the key characteristics of your specific piece.

ONGEMS certificate of authenticity

What the certificate states

  • Item name — for example, Letter Charm P
  • Metal and fineness — for example, white gold 750
  • Stone type and quality — natural or lab-grown diamond, colour and clarity
  • Total weight of the piece
  • Date of issue and authorised signature

The certificate is issued for each gold piece individually and is included in the package together with your order.

Materials we use

  • Gold collection: gold 750 (18k) — yellow, rose or white; set with natural or lab-grown diamonds of your choice.
  • Silver collection: sterling silver 925, set with cubic zirconia.

About lab-grown diamonds

Lab-grown diamonds have the same chemical composition, crystal structure, hardness and brilliance as natural diamonds. The difference lies only in their origin: they are created in a laboratory rather than mined. The type of diamond in your piece is always stated in the product option you select and in the certificate.

Questions about a specific piece?

Write to us at hello@ongems.store or on Instagram @on_gems — we will tell you everything about the materials and characteristics of the piece before you order.