Old cut diamonds: what you have actually inherited

The round diamond almost everyone pictures was settled in 1919. The Jewellery Editor's Diamond cuts: a definitive guide, by Jordan Clary, 1 March 2015, puts it plainly: in 1919 Marcel Tolkowsky improved on the cut by following the shape of the rough crystal, and the round brilliant carries 57 or 58 facets. Every diamond cut before that year was worked to different rules. So the stone in your grandmother's ring is not a failed modern diamond. It is an older kind of diamond, and it was never trying to do the same job.

I have made jewellery by hand in London for 22 years, from a stall on Portobello Road to counters at Liberty, Selfridges, Harvey Nichols and Harrods. Many inherited rings have crossed my bench, and the thing almost nobody has been told is what they are holding.

The three old cuts you are most likely to own

The rose cut. Flat underneath, domed on top, a small number of triangular facets rising to a point. There is no deep base to bounce light back at you, so a rose cut glows rather than flashes. Georgian and Victorian pieces are full of them, often ringing a larger stone.

The old mine cut. Writing on Victorian engagement rings for The Jewellery Editor on 3 April 2015, Åse Anderson dates this cut to the 1700s and notes that it resembles the modern cushion cut. A squarish outline, soft corners, a high top and a small flat face.

The old European cut. Round, and described in that same piece as a 58 facet cut and the predecessor of today's round brilliant. It is the one mistaken for a modern stone, right up until you look down into it.

Why an old stone looks different

All of these were cut by hand, before power tools and before anyone had worked out the mathematics of how light travels inside a diamond. The cutter followed the rough and kept as much weight as possible. That leaves fewer and larger facets, a taller crown, a smaller flat face on top, and often an open culet, a tiny flat facet at the point underneath that reads as a small window when you look straight down into the stone.

The effect is broad, slow flashes instead of fine, fast sparkle. By candlelight that is exactly right, because candlelight is what these stones were cut to live in. Under a modern spotlight a new brilliant will out-sparkle an old European cut every time, which tells you about the lighting and nothing about the diamond.

What a diamond costs in something new

The question after what have I got is usually what a new one costs, and that depends on what the stone is. My Diamond Huggie Hoops make the point better than I can. They are 1cm across. In sterling silver they are £70 and the stones are cubic zirconia. In 14kt solid white gold they are £550, set with 0.25ct of genuine diamonds. Same shape, same bench, two quite different things, and the listing says which is which. Many pages in this trade do not.

Then the decision nobody warns you about

When an old ring comes in there are only ever two routes. Keep the piece whole, repair what needs repairing and wear it as it is. Or lift the stones and set them into something you will actually put on. The two are not reversible in the same way, and that is worth saying out loud: once a stone leaves its old setting, that setting has gone.

So the question is not which looks better. It is whether the object matters more, or wearing the stones does. If it is the stones, my Second Life Jewellery service is the heirloom remodelling side of the workshop, and its page says what I believe most: old diamonds do not need to look old-fashioned. Send a photograph and I will tell you what it could become and what it would cost. The estimate is free and there is no obligation. Loose stones, odd earrings, a broken chain, a ring that has sat in a drawer for 30 years, all of it counts.

If it is gold with nothing worth keeping in it, recycling your old jewellery is the other route, and carries a £20 voucher.

Two more ways in

For everyday wear the Diamond by the Yard Necklace is £100 in sterling silver or gold vermeil, set with brilliant round cubic zirconias. Lighter again, the Mina Huggie Hoops are £50 in sterling silver and £65 in gold or rose gold vermeil. At the other end the Oval Diamond Locket is £550, set with a diamond at its centre and made to be added to any of my necklaces or bracelets, and the Solid Gold Diamond by the Yard Necklace runs £750 for 0.30 carat and £1,500 for a full carat in 14kt solid gold. If you are hanging a locket on a chain, the Chain Guide explains why a chain is measured without the pendant, which adds roughly 0.75in to 2in.

The second life is the real one.

Everything set with diamonds and crystals is in the Diamonds collection, the solid gold pieces in 9kt Solid Gold, and if you have an old stone and no idea what to do with it, send me a photograph through Second Life Jewellery. Anna Lou x.

Questions I get asked

How do I tell whether my inherited diamond is an old cut?

Look straight down through the top of the stone in good light. An open culet shows as a small window right at the centre, and the facets will look fewer and larger than on a modern stone. A high crown and a small flat face on top point the same way. Any jeweller can tell you in seconds, and most old stones have no certificate, because they were cut long before grading reports existed.

Can an old cut diamond be reset into something modern?

Yes, and it is a great deal of what the workshop does. The stone is checked first, because an old stone can carry small chips at the edge from a century of wear and that affects how it can be held. If it is a ring you are having made, the Ring Size Guide shows how to measure at home. Send a photograph to Second Life Jewellery first and you will have an estimate before you commit to anything.

Is a cubic zirconia piece worth buying?

For everyday wear, often yes. It is a real piece of handmade jewellery in recycled sterling silver or vermeil, and it costs a fraction of the diamond version, so it can be worn without thinking about it. What matters is that the listing tells you honestly which is which, as on the Diamond Huggie Hoops, where the silver pair is set with cubic zirconia and the solid gold pair with genuine diamonds.