The size of a collection comes down to the number of pieces that can be made. “It’s very rare to have jewellers at this level of knowledge to make this kind of piece,” Karachi says. “If we have no hands, we can’t do jewels.”

Cartier chief executive Cyrille Vigneron acknowledges that high jewellery is not the maison’s most profitable category; one piece can take up to “a few thousand hours” to make.

“But in terms of image building, it’s the most beautiful thing we can do,” he says. “It plays a very important role in creating identity and creating our point of view in the world. And we don’t want to expand too much.”

Paradoxically, he believes high jewellery is inclusive because international exhibitions of rare Cartier pieces tend to draw huge attendances. In 2019, Beyond Boundaries in Beijing attracted 600,000 visitors, and in 2018, Cartier: The Exhibition broke the attendance record at the National Gallery of Australia. “In some way, it’s the most exclusive and the most inclusive category. Anyone can appreciate it for its beauty.”

The growth category, however, is fine jewellery: limited series, small quantities, but in sufficiently large numbers that customers get to know and feel comfortable with the brand. It is the feeder category to high jewellery.

“It’s the same as buying art,” Vigneron says. “You go step by step until you feel confident enough to say, ‘I want to make a big investment or a purchase for my house or my museum or whatever.’”

Vigneron became head of Cartier, the jewel in the crown of luxury conglomerate Richemont, in 2016. His philosophy, that the company has a responsibility to maintain beauty wherever it is found, is why he puts aesthetics first. Even if it means stopping production on a line that is selling well.

“Six years ago, Cartier dispersed into areas which were not typically Cartier, and customers were a bit lost,” he says. “The worst for a maison like Cartier is to do something that sells but which someone else could do. I say, ‘Don’t make anything ugly. Because at some point the customer might buy it, and they will never forgive us.’ It may sound frivolous, but in fact it’s a very strong commitment.”

Vigneron is overseeing an increase in business across all Cartier’s markets, partly a consequence of pent-up demand from lockdowns. Shoppers, he says, are seeking exclusivity and special treatment like never before. The answer to this, from some top brands, is private boutiques for VIP customers, but that’s not in Vigneron’s model.

“We don’t think we need to make a specific private boutique. When you advertise it’s private, it’s not private. But there are some parts of our boutiques where not every door is visible, like in a private house.”

Cartier will soon open a new flagship boutique in Sydney’s George Street. The ground level will be for jewellery for men and women. Upstairs will be an exhibition space, a cocktail lounge, private VIP viewing salons and a digital studio for consultations with regional clients, with e-commerce capability for immediate dispatch.

Cartier managing director Australia and New Zealand Alban du Mesnil says the existing flagship, in Castlereagh Street, will stay open for now, a mark of how strong the brand has become in this country. Its future role might include collaborations with artists.

Vigneron says people want things that are meaningful. “And so the more luxury gets basically everywhere, the more people want something very special.” Which is why, this year, special for Cartier can mean mixing precious stones with less precious and decorative stones in the creation of its high jewellery collection. Opals, for instance.

Says Karachi: “The most important thing is that the stones are natural. Today we are more open-minded about stones, so we have more freedom and that opens a lot of opportunities for us to evolve.”

Happily for Karachi, she is seeing her creations being worn more often and by a wider age range of clients. “The young generation travel more and have no problem wearing very expensive pieces of jewellery. Before, their elders put them in the safe. Today, they are more free. I like it this way.”

She might just see Apatura on her travels some time soon, too, because it was snapped up in Madrid.

The writer was a guest of Cartier

The spring issue of Fin Magazine is out on Friday, August 19 inside The Australian Financial Review.