Diamonds are not manufactured, they occur naturally. They are also all unique and, unlike precious metals, are not stamped with hallmarks. Certification therefore provides a system that can be used to grade diamonds and to reassure clients of their authenticity and value before they purchase.

Certified diamonds are always accompanied by a certificate proving they have been inspected and graded by an independent gemmological laboratory. Hearts of London only sells high quality diamonds that have been independently inspected by the Gemological Institute of America (GIA), Hoge Raad Voor Diamant (The Diamond High Council) (HRD) or International Gemmological Institute (IGI), placing them among the most desirable and sought after diamonds available.

Before being certified, a diamond will be weighed, measured and examined using a microscope and other gemmological instruments. A diamond certificate will be issued providing detailed information about the diamond’s size, shape, colour, carat weight and cut. The report will also confirm that the diamond has been produced naturally and not in a laboratory and that it has not been artificially enhanced to improve its colour or clarity.

A grading report will also provide important information about a diamond’s polish, symmetry, girdle thickness and overall proportions. Larger diamonds will come with a plot map, highlighting the type and position of any inclusions that may be present.

  • Get the Flash Player to see this player.

    In order to offer clients the finest quality diamonds, we ensure that every stone is also inspected by our own gemmologist who is a highly skilled diamond grader. Only those diamonds that pass our stringent selection processes will be sold or set into jewellery. Any that are rejected will be immediately returned to be used elsewhere.

Many retailers will provide their own diamond certification. We strongly advise clients not to purchase self-certified diamonds as these are often over-graded by the retailer and passed off as being of a better quality than they actually are. Jewellers who certify their own diamonds may for example exaggerate the colour and clarity grades leaving the customer paying for quality that simply is not there.

Furthermore, not all grading laboratories employ the same stringent processes. The GIA, HDR and IGI are renowned as the most respected, consistent and rigorous in the world. Reassuringly for our clients, Hearts of London only sells diamonds that have been certificated by these laboratories.

Hearts of London offers access to 25,000 certified diamonds and allows clients to take advantage of the lowest prices in London. Our certified diamonds are sourced from quality assured suppliers and are guaranteed to be conflict free.

The certificates that appear if you click our 'download automated certificate’ button are automatically generated using details from our database. Due to the fast turnover of our diamond stock, it is not possible for us to scan the actual certificate of every diamond in our database. We will however happily fax or e-mail you a copy of the original certificate. Please use the request original report button to obtain the original grading report.