Diamond with certificate
Blog / Gemstones

Why aren’t all diamonds certified?

Friday May 28, 2021
Stephen Sutton

When choosing a diamond, should you ever buy without a certificate?

Well, we could argue both yes and no.

Are all certified diamonds better quality than those not certified? No. Many lower-quality diamonds can be independently sold with a certificate, whilst others (for many reasons) will not. These aren’t necessarily inferior to those that are certified, just that they don’t have a laboratory’s printed out statement of their opinion.

We at Cry for the Moon have both, and we happily buy new and pre-owned certified and non certified diamonds.

It’s a much discussed subject, and as such, there are many different opinions surrounding it. The majority consensus is that you should purchase diamonds with a certificate, and that it should be GIA or HRD. It’s also often stated that certain laboratories should be avoided as they aren’t terribly accurate at best, and misleading at worst. Many jewellers provide and/or produce their own in-house variations, including none other than Tiffany’s… so it must be correct, right?

What is the standard?

Well, there is in fact no internationally recognised standard – and more importantly – no one body that regulates the independent labs for verification of grading quality. We aren’t suggesting that the laboratories are wrong, but a study published in July 2013 (page 74-75), by the NAG (National Association of Goldsmiths) and Gem-A (Gemology Association of Great Britain) (page 74-75) found great variations in the grading. Seven previously graded GIA diamonds were sent to six independent UK labs for certification, and the results were quite alarming. In many cases, both the colour and clarity results varied by a number of grades – which would likely alter the price by 20-25% at retail.

Perhaps GIA had graded some of the diamonds to a better standard now than they had 20 years ago, suggesting a softening in the required standard, or perhaps it is that the grading is slightly subjective, with the human factor not allowing 100% accuracy. Let’s face it, diamonds tend to speak for themselves – you don’t walk around with a piece of paper around your neck or in your handbag to show off the colour… and as soon as it’s worn it becomes dirty, affecting the colour and clarity anyway.

Where do we buy our diamonds from?

We have, for many years, purchased diamonds direct from our supplier in Antwerp who have their own source of approved, traceable diamonds that have up-held the Kimberly process. Kathy, Stephen & Harry (who choose and buy all our loose diamonds) have over 100 years of experience between purchasing and grading stock. We are extremely confident in our process of assessing and grading both new and loose diamonds, and happily supply our own valuation stating an honest opinion of the diamond’s grading.

Another point to bear in mind is that diamonds are graded against other diamonds, so the cut and proportions will affect the stone as much as other factors, which is why it’s very important to physically see the diamond for yourself and make your own decision.Be it certified or not, we have a fabulous range in stock at all times – in many different styles and designs across rings, pendants and earrings.

If you would like to see for yourself, please pop into our shop and ask one of our sales team to show you our stunning collection. Any one of the team would be happy to share knowledge on anything you might like to know – to help you make up your own mind. Buying a diamond should always be an exciting, romantic and pleasurable experience. Contact us today to book your appointment, or simply come in to the shop.

Stephen SuttonHead of Sales