When Marilyn Monroe huskily breathed her way through Diamonds Are a Girl’s Best Friend, she was putting into words an upscale approach to love, marriage and infidelity that insisted on a currency of carbon. Similar superstars, from Ethel Merman, Jayne Mansfield and Elizabeth Taylor to Vivienne Blaine and Elaine Stritch, acted out the showbiz cliché that guys must always pay for their pleasures.

In the days when a woman’s honour was her highest bargaining counter, if she were to lose it without the benefit of a wedding ring, she would make damn sure she extracted a high price for it. Exchanging money was considered sordid, so the French — who know all about sin — invented payment by luxurious gift. For Americans, that always meant diamonds. Popular myths maintain that the greatest jewellers in Paris, Monte Carlo and New York were kept in business by men buying diamonds for their mistresses and not their wives, who usually made do with a tasteful solitaire for their engagement and maybe some earrings or a clip when a son and heir came along (“There’s a clever girl” — ker-ching).

Thanks to the ghetto’s love of bling, diamonds have been seriously devalued in the mistress stakes. Despite this, their aura still prevails. Now, though, it’s the alpha female (in a statement of exemplary independence) who is buying — and, with a smaller budget, opts for something rather more modest and tasteful, with cut being more important than size. One jeweller that understands both sides of the taste gap is the American firm Harry Winston, which has been responsible for some of the more spectacular diamond jewellery of the past few years. On Tuesday, it opens its first British store at 171 New Bond Street (020 7907 8800).

Whether vulgar or refined, diamonds will always be a good investment. Take it from Marilyn: “Get that ice or else no dice.”

Times recommends

• Live chat: Thrifty ways to update your winter wardrobe
• Is anybody out there really listening?
• Nutrition Q&A: Will eating late make me fat?