The conventional calendar used in most of the world is the Gregorian calendar, which has 365 days and an extra day in February every leap year. Consequently, and quite sensibly, almost all calendar watches display the Gregorian calendar. But there are other calendars used by various cultures and countries, like the Japanese calendar used for its Imperial eras, and also the Islamic, or Hijri, calendar.

And now for the very first time, Parmigiani Fleurier has created a wristwatch with a Hijri perpetual calendar. Founded in 1996 by watchmaker Michel Parmigiani, the brand has long been synonymous with inventive and complex watches, most notably the supercar-inspired Bugatti timepieces.

In 2011, the brand unveiled the Hijri calendar table clock, a US$2.5 million creation elaborately constructed in silver, rock crystal and semiprecious stone. Now Parmigiani has refined the concept and miniaturised it for the wrist with the Tonda Hijri Perpetual Calendar.

A lunar calendar

Made up of 12 lunar months and used to track important dates and events in Islam, the Hijri calendar differs from the common Gregorian Calendar in being a lunar calendar, one based on the cycles of the moon, and not Earth’s revolution around the sun. Its 12 months have either 29 or 30 days, resulting in a year that’s between 10 and 12 days shorter than the conventional 365-day year.

The Islamic calendar began in 622 AD when the Prophet Muhammad moved from Mecca to Medina, both in present-day Saudi Arabia, and founded the first Islamic community. In the millennia that the Hijri calendar has been in use, it is not known to have been integrated into a mechanical perpetual calendar wristwatch. While several watchmakers have built Hijri calendar wristwatches in the past, including Konstantin Chaykin and Daniel Roth for Breguet, those were not perpetual calendars, making Parmigiani’s new watch a world first.

Precious, sans gold

Soberly dressed in shades of grey and silver, the Hijri Perpetual Calendar has a polished platinum case measuring 44.5mm in diameter and 14.09mm in height. Gold was specifically avoided as it’s an Islamic tradition that men cannot wear jewellery, and by extension, gold – not one element of the watch is in gold.

Hours and minutes are indicated by large, open-worked hands, while the seconds hand features a counterweight shaped like a crescent, often used as symbol of Islam and found on flags of Islamic states (although the religion has no official emblem).

The Hijri calendar is a full calendar, showing the date in Eastern Arabic numerals at nine o’clock, along with the names and lengths of the months in Arabic at three, as well as the years at 12. And at six is the moon phase display, with the moon disc in aventurine glass.

The month in red at three o’clock is Ramadan, the month of fasting and prayer

Two recessed pushers for setting the calendar

Inside is the in-house PF009, which has a 48-hour power reserve. Though the mechanics of the movement are identical to the standard calibre, elements for the movement were redesigned to incorporate elements inspired by Arabic architecture. The bridges, for instance, incorporate the shape of a crescent as well as the the Islamic symbol Rub el Hizb, two overlapping squares forming a star. And the rotor is in black-coated platinum, decorated with barleycorn guilloché.

Key facts and price

Hijri Perpetual Calendar
Ref. PFH980-2000110-HA1482

Case diameter: 44.5mm
Height: 14.09
Material: Platinum
Water resistance: 30m

Movement: PF009
Functions: Hours, minutes, seconds, Hijri perpetual calendar and moon phase
Frequency: 28,800 beats per hour (4Hz)
Winding: Automatic
Power reserve: 48 hours

Strap: Hermès alligator strap with pin buckle

Availability: At Parmigiani boutiques and retailers starting April 2020
Price: US$80,000, or 108,281 Singapore dollars

For more, visit parmigiani.com

As crucial to Jaeger-LeCoultre’s identity as the swivelling Reverso wristwatch, the Atmos clock remains a unique and intriguing invention almost a century after its invention – a clock that runs on air. Having been offered in a variety of iterations over the years, including several by industrial designer Marc Newson, the latest is the Atmos Transparente, a clean, modernist reinterpretation of a longstanding model in the line-up.

Despite being synonymous with Jaeger-LeCoultre, the Atmos was actually invented by someone else, who was inspired by a much older idea. Clocks wound by changes in atmospheric temperature were invented sometime in the 17th century, but remained largely experimental until French engineer Jean-Léon Reutter invented the Atmos in 1928. His idea was actually an evolution on the 400-day clock, which is regulated by an exceptionally slow pendulum and need only be wound once a year.

The magic of air

The genius of Reutter’s invention was a sealed metal bellows containing mercury, which expanded and contracted with changes in temperature, thus winding the clock’s mainspring. Despite its novelty, Reutter’s clock met with little commercial success – early Atmos clocks marked “J.L. Reutter” are rare but not especially valuable – leading him to sell the idea to LeCoultre in 1935 (and two years later the company joined forces with Edmond Jaeger to form Jaeger-LeCoultre).

The company refined his concept, with the key improvement being the replacement of mercury with ethyl chloride gas, which improved the clock’s winding efficiency and reliability. Since then the Atmos has become a steady seller over the decades, as well as an official gift of the Swiss government.

Though identical in shape – essentially a glass box on a rectangular steel base – the facelifted Atmos Transparente is simpler and sleeker than its predecessor. Black baton hour markers have replaced the Roman numerals of the original, matched with glossy black hands.

All of the mechanics that drive the Atmos as visible, including the gas-filled bellows on the back, as well as the extra-large – and extra-slow – balance wheel at the base. With the large balance making just 120 oscillations per hour – compared to 28,800 in a standard mechanical wristwatch movement – the Atmos movement runs at a leisurely pace that allows it to continue quietly for decades.

The bellows (top right) and the balance wheel

At US$9,450, the Transparente is priced significantly above the entry-level Atmos Classique that costs US$6,600, but is probably a more compelling proposition because of its contemporary styling that will fit most homes better than the old-fashioned – and out-dated – look of the base models.

Key facts and price

Atmos Transparente
Ref. Q5135204

Dimensions: 250mm by 185mm by 145mm
Material: Glass with antireflective coating, on a steel base

Movement: Cal. 563
Functions: Hours and minutes
Winding: Via changes in ambient temperature
Frequency: 120 beats per hour
Power reserve: “Virtually perpetual”

Availability: Jaeger-LeCoultre boutiques and authorised retailers
Price: US$9,450

For more, visit Jaeger-lecoultre.com.