A life with diamonds

Receive useful information about diamonds and diamond jewellery before, during and after your purchase.

Read more about how to treat your jewellery to get pleasure from it for the longest possible time. Learn more about the 4 Cs, certificates and engraving options and be inspired by Hartmann’s many publications.

Diamond valuation

Diamond Guide

When a diamond is valued and classified, it is done on the basis of the 4 Cs. It is a form of product information that describes the characteristics of the diamond.


tells you about the size; the carat weight


describes the cut, which is instrumental in how much scintillation and brilliance the diamond will have


describes the diamond’s clarity. Is the diamond clean, or are there are many inclusions?


indicates the colour of the diamond

Care and maintenance of your jewellery

Jewellery Guide

A piece of Hartmann’s jewellery represents fine craftmanship – so treat it with care. To avoid unnecessary wear, knocks and bumps to your jewellery, we would like to provide a few guidelines for the use, storage and maintenance of jewellery from Hartmann’s.

The piece can of course be worn daily, but we recommend that you remove it when you:

  • Play sports
  • Sleep
  • Bathe
  • Do housework or gardening
  • Perform other activities in daily life that can cause accidental damage to the jewellery


Hartmann’s jewellery is graded by trained diamond graders in our workshop. Each piece of diamond jewellery therefore comes with a Hartmann’s certificate describing the piece based on the 4 Cs. The certificate that accompanies the piece is a type of declaration that is valid throughout the entire world.

If the piece has a white diamond of more than 0.40ct, it will also come with an international grading report from the GIA or HRD.

Make your rings unique


Both the location of the engraving and the choice of text provide multiple options to make the rings unique, and it is also possible to choose the font.

Perhaps you prefer cursive script, reminiscent of personal handwriting? Or perhaps you prefer simpler printed letters?

How to find

Finding the ring size

If you are uncertain about the size of a ring, you can find help here.

There may be times when you need to know what size your ring is. You may also need to secretly measure another person’s ring size in preparation for a marriage proposal or gift.

There are various methods you can use to measure ring size.

Inspiration for you

Catalogues and publications

Discover the unique diamond collections that we have designed over the years. Get inspiration from our Argyle Pink jewellery, jewellery with white diamonds, or from our extensive earring catalogue.

If you are planning to propose or are seeking inspiration for wedding bands, you can download our catalogue.

The shop’s opening hours

View detailed opening hours
  • Monday 10:00 to 5:30
  • Tuesday 10:00 to 5:30
  • Wednesday 10:00 to 5:30
  • Thursday and Friday 10:00 to 5:30
  • Saturday 10:00 to 2:00

Request a call back

Visit our shop and get expert advice from one of our employees.

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