Shopping for an engagement ring is a truly nerve-shredding experience. If, peering anxiously into the jeweller’s window, you find yourself casting about for someone to blame for this sorry state of affairs, try Frances Gerety. One night, in 1947, the young copywriter sat at her desk in the empty Philadelphia office of N. W. Ayer & Son and stared with increasing desperation at a picture of two honeymooning sweethearts. In a couple of hours, she was due to reveal a tagline for a series of engagement-ring advertisements commissioned by De Beers (which mined the majority of the world’s diamonds), but she hadn’t managed to come up with so much as a syllable. Finally, she scribbled ‘A diamond is forever’ on the piece of paper, packed up and went home.

She could never have predicted what would happen next. Within months, the immortal phrase had become De Beers’s official slogan and people’s attitudes towards engagement rings had changed forever. Before Miss Gerety came along, splashing out on one had been considered wildly extravagant, wasteful even-a luxury reserved for Hollywood stars and titans of industry. But her magic words made buying the finest and most beautiful piece you could afford a romantic imperative. It was also N. W. Ayer & Son which created the expectation, through another campaign, that a man should aim to spend two months’ salary on it.

The path to getting a band onto your beloved’s finger is a many-forked one. Are you planning to propose with it or to visit the jeweller à deux to choose one together after the event? And, if you’re going ahead under your own steam, will you be commissioning a brand-new design, buying
an existing band or plumping for a family ring? Whichever route you take, one thing’s for certain: this is not the time for leaps of faith. ‘If you’re looking to have a ring made, you need to be absolutely certain that the design you’re commissioning is what the lady wants,’ counsels Omar Vaja of Bentley & Skinner (www.bentley-skinner.co.uk; 020-7629 0651).

Exchanging a bespoke piece for something else will be extremely difficult, if not impossible. Study the contents of her jewellery box, keep an ear open for hints and consider enlisting her friends as accomplices. You’ll also need to allow at least six weeks for your initial sketch to be turned into a piece of jewellery-worth keeping in mind if you’re hoping to propose on a particular date.

Mr Vaja’s top tip for grooms-to-be buying ‘off the peg’ is that bigger isn’t always better-quite the opposite, in fact. ‘Go for something that’s practical,’ he advises. ‘If it’s too large and dressy, she won’t feel able to wear it on a daily basis.’ High fashion is also best avoided. ‘The ring needs to be timeless, too, something that will age with the wearer.’ And checking whether the jeweller is prepared for a not-quite-right ring to be returned and swapped for another before you commit will provide much-needed peace of mind.

Surprises are romantic, as any fool knows. But, when it comes to ring-buying, they’re also fraught with the potential for disaster, as 28-year-old Sadie Macleod, editor of online lifestyle magazine Hip & Healthy, will tell you. Her boyfriend Nick Reid, a solicitor, had always known that his loved one’s heart was set on a rare yellow diamond. After months of searching, Boodles (020-7493 3240; www.boodles.com) finally managed to procure one for him in New York, which was then set on a band made to his specifications. All there was left to do, he hoped, was wait for the perfect moment to pop the question.

Not long afterwards, Miss Macleod went away on holiday with a friend, who counselled her to go for another stone if she ever wanted to get engaged-yellow diamonds, she told her, were maddeningly difficult to get hold of.

Miss Macleod took this warning to heart and, when she came home, mentioned casually that she’d decided she wasn’t that fussed about yellow diamonds after all and would much prefer a white one. ‘Nick got straight on the phone to Boodles and said “Hold that thought”,’ remembers Miss Macleod. ‘Then, he rushed off to another jeweller to get a white-diamond ring.’ However, at a friend’s wedding over the Diamond Jubilee weekend, he realised that he had made a terrible mistake-the new ring, beautiful though it was, meant nothing to him. He and Miss Macleod were meant to be flying out to Florence later that day, where he’d planned to propose to her in the Boboli Gardens.

Thus began a race against time to rescue the original ring, which, by this point, was locked in a safe at the Royal Exchange. ‘The shop was shut, but Nick somehow managed to get hold of someone from Boodles and they drove into the City together to get it,’ Miss Macleod recalls. Thankfully, their mission was successful and Mr Reid was able to go down on one knee in Florence as planned. Miss Macleod cherishes her engagement ring, which, she says, ‘shows Nick’s tenacity’.

An increasingly popular alternative to proposing with a family ring is creating one together out of rings from both families. Symbolically, it’s a powerful representation of two people’s respect for the legacy of previous generations and desire to build on it during their life together. ‘The ring is a union in itself,’ says Guy Robertson (020-7735 7529; www.guyrobertsondesign.co.uk), who designed for big-name houses such as Links, Boodles and Garrard before going freelance. ‘It can bring new life and meaning to pieces that otherwise wouldn’t be worn, too. But don’t feel you have to use every stone-there’s potential for a piece to look crowded. Decide which elements you love and take advice on how to bring these together.’

The best things in life frequently come in unexpected forms. For 31-year-old vet Caroline Chamberlin, the perfect ring turned out to be a million miles away from the one she’d imagined. ‘I think I’d always unwittingly assumed that I’d end up with something period that had a bit of colour in it-an Art Deco piece with sapphires or emeralds,’ she explains, ‘the sort of thing lots of my friends have.’ In the event, she found herself gazing at a series of rogue diamonds set on a slim, yellow-gold band. It had been made by Garrard and passed down through her boyfriend’s family for generations. ‘When I opened the box, what I was looking at wasn’t what I’d expected to see,’ she admits. ‘But I fell in love with its simplicity and history. It’s a very humbling thing to be given.’

Ring true: beautiful bands

Bespoke engagement rings, from £2,500 (this model, with sapphire and diamonds, £12,000), W&W Jewellery (www.wandwjewellery.com; 020-7924 2386)

Grosvenor-style diamond ring from 1745 collection, from £2,500, Heming (020-7499 7644; www.hemingjewels.com)

Antique platinum-emerald-and-diamond ring, price on application, Lucie Campbell (020-7629 4647; www.luciecampbell.com)

Coronet-set three-stone diamond-and-platinum ring, £7,820, George Pragnell (01789 267072; www.pragnell.co.uk)

Double vintage Ashoka diamond ring set in platinum, from £13,000, Boodles (www.boodles.com; 020-7437 5050) 

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