Questions You Should Always Ask Your Jeweller - But Most People Don't

GIA and IGI are the two certification bodies worth trusting. An uncertified diamond is an unlabelled bottle — the contents may be exactly what you were told, but you have no independent way to verify it. A grading report tells you the stone’s cut, colour, clarity, and carat, assessed by a third party with no stake in the sale.

Ask to see the certificate. It should match the stone. Any jeweller who cannot produce one — or is vague about which lab issued it — is offering you trust without the means to verify it.

Not the shape. Not whether it’s a round or an oval. The quality of the cut — the grade that determines how the stone interacts with light. Cut is the most consequential of the 4 Cs, and it is the one most often glossed over in a sales conversation.

The answer you want is Excellent or Very Good. If a jeweller has to check, or pivots to talking about the shape, or gives you an answer about brilliance or sparkle without naming a grade — that tells you something. A Good or Fair cut, even on a technically impressive stone, will disappoint you every day.

You should always know which you are being shown. The price difference between a lab grown and a natural diamond of equivalent quality is significant — typically 50 to 70 percent. This is not a minor detail. A jeweller should volunteer this immediately, without being asked. If they haven’t, ask directly. The answer should come without hesitation, and with a clear explanation of the implications of both.

Not the diamond — the ring itself. This question is about craft, not geography. Hand-set stones are checked by human eyes, one prong at a time. Machine-set stones move faster, and the difference is visible in longevity — in how prongs hold over years of wear, how stones sit, how the setting ages.

Both methods have their place. But you should know which you are buying. A jeweller who is proud of their craft will tell you without being asked. One who is vague about it has told you something by being vague.

The lighting above a jeweller’s display counter is designed to make diamonds look their best. Halogen, focused, bright. It is doing significant work on your behalf. A diamond that only performs under that light is not performing — it is being performed for.

Ask to step toward a window. Ask to see it under a standard bulb. If possible, ask to take it outside for a moment. A stone with genuine life will show it in all of them. The difference between a stone that thrills you in the shop and disappoints you at dinner is often answered in this one question.

Resizing, prong tightening, polishing, cleaning — who handles these, for how long, and at what cost? A ring worn every day for fifty years will need occasional attention. That is not a flaw; it is physics. The question is who stands behind the piece when it does.

A jeweller who is clear and generous on this point is one who makes rings they expect to last and is confident saying so. A jeweller who is vague has thought carefully about being vague.

This is the most important question on this list. And the one most people never ask.

A good jeweller can tell you precisely why one stone is right for your budget, your taste, and your partner’s hand. The answer will reference something specific — the cut grade in relation to the setting, the colour in relation to the metal, the clarity in relation to the shape. It will not sound like a script. It will sound like someone who knows what they are looking at and has applied that knowledge to you, specifically.

If the answer is vague, that is the answer.