So often the horology world is prone to overspeak. But as Patek Philippe celebrated the 50th anniversary of the Golden Ellipse in 2018, Thierry Stern, now president, couldn’t have put it better when he remarked: ‘It’s one of those watches that shows you how to make a Patek Philippe. No gimmicks, just purity and beauty expressed through simple design.’

Debuting in 1968, on the cusp of the jet-set age, and still in production today after many iterations, the shape of the Golden Ellipse – a rounded rectangle – was innovative, a bold departure from traditional watch shapes. It wasn’t following fashion but striking out confidently on its own. More than pleasing to the eye, it possesses a sense of harmony. This is explained by the design taking its inspiration from the mathematical principle of aesthetic proportion. Discovered by Ancient Greek mathematicians including Euclid, “the golden section” – expressed as a ratio of 1/1.6181 – is said to form the basis of some of history’s greatest works of art and architecture, including the Parthenon in Athens. The Renaissance mathematician Luca Pacioli found the proportions of this design principle – that dictates the perfect point at which to divide a line into two harmonious but unequal lengths – so flawless that he renamed it ‘the divine proportion’.

The aesthetic rule of the Golden Section has also historically been noted as manifesting in nature, in the shape of leaves, the spacing of buds along a branch – and the proportions of the human body. It’s also been claimed it was a guarded secret passed from master to pupil for builders of Hellenic temples and the great churches of the middle ages.

However the design concept narrative runs, there’s surely no contention that it’s simply beautiful and timeless. The Golden Ellipse manages paradoxically to be both forward looking and classic, which explains its enduring appeal. The design remains unique in Patek Philippe’s timepiece portfolio. When the glamorous watch first appeared it became a symbol of international chic. Testament to the strength and adaptability of the design, a family of other watches with a similar aesthetic was built around it, and a range of accessories – lighters, cufflinks, tie clips, key chains – that became highly collectable, like the watches.

This year the Golden Ellipse Ref 5738/1R, the only version now being produced, is celebrated with its first metal bracelet. The elegant, supple, chain-style bracelet in rose gold pays tribute to the 1970s, the Golden Ellipse’s most celebrated era. It features more than 300 rose-gold links set in fine rows, individually hand mounted. The watch itself, in a size once referred to as “jumbo”, has a sunburst ebony dial decorated with applied baton-style hour markers and slim hands in rose gold. The 18k rose-gold case, a slender 5.9mm, houses the ultra-thin self-winding mechanical movement, Caliber 240.

The Golden Ellipse may now be playing a cameo part compared with its ’70s heyday in the starring role, but it still finds a way to be in the spotlight. The camera loves it – and so do we. This is its latest production and it’s ready for its closeup.

£51,470; patek.com