Monochrome Watches
An online magazine dedicated to fine watches
Buying Guide

From Time & Date Watches To Secular Calendars And Everything In Between

Upping the complexity one calendar watch at a time.

| By Robin Nooy | 8 min read |
Patek Philippe 5320G Salmon Dial Perpetual Calendar

As we’re coming up to the end of February, our nerdy watchmaking minds always tend to stray in the direction of Perpetual Calendar watches. And even though this year is not a leap year, the fact that a watch can switch from the 28th or the 29th of February to the 1st of March without any corrections is absolutely fascinating to us. But calendar watches, in general, not just QP’s, serve a very practical goal: keeping you informed of other calendar indications besides ‘just’ the passing of time. So from a basic time-and-date model as a start and a secular calendar at the end, today’s Buying Guide goes from the simplest calendar watch to the most complex. 

Time & Date – Oris Big Crown Calibre 473

One of the earliest time-and-date wristwatches, and quite an iconic one for that matter, is the Oris Big Crown Pointer Date. Born in 1938 and in production pretty much ever since, it has a strong following of fans. What started as an early pilot’s watch has grown into a cornerstone model for Oris, solidified by the latest Big Crown Calibre 473. This offers a contemporary twist to the classical style of the Big Crown and the emblematic Pointer Date complication and merges it with the brand’s new in-house calibre 473. As a bonus, you get a hidden power reserve indication at the back. At CHF 4,200, it’s by no means cheap, but it is the most affordable watch on today’s list.

Oris Big Crown Calibre 473

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Quick Facts – 38mm diameter – stainless steel case, polished & brushed – flat bezel – oversized screw-down crown – domed sapphire crystal – sapphire crystal caseback – 50m water-resistant – blue dial with printed indices and numerals – sword-shaped hour and minute hands – small seconds – red-tipped pointer date hand – calibre 473, in-house – manual winding – 120h power reserve – patented power reserve indicator – hours, minutes, small seconds, date – Cervo Volante deer hide leather strap with folding buckle – CHF 4,200

Day-Date – Rolex Day-Date 40mm Platinum 228236

The Rolex Day-Date is, simply put, a true watchmaking legend. It was the very first wristwatch that indicated the day of the week in full next to the time and date. In production since 1956, it is one of the most classical models in Rolex’s arsenal. Last year saw the introduction of the full platinum Day-Date 40mm 228236, which also introduced the first-ever platinum fluted bezel! The date is magnified under the cyclops, with the day of the week nestled between the 11 and 1 o’clock applied hour indices. It comes with Rolex’s latest generation calibre 3255 automatic movement, and is worn on a platinum President bracelet. The price is on request, as with all platinum watches by Rolex.

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Quick Facts – 40mm diameter – full platinum case, bezel and bracelet – Twinlock screw-down crown – sapphire crystal with cyclops – 100m water-resistant – black, slate, ice blue, olive green, white, silver, meteorite or diamond-paved dials – applied Roman numerals and stick indices and/or baguette indices- arched date window – calibre 3255, automatic – Chronergy escapement – 70h power reserve – hours, minutes, seconds, date, day of the week – platinum President bracelet – Price on request

Complete Calendar – Christiaan van der Klaauw Ariadne

Under the tutelage of master watchmaker Pim Koeslag, Christiaan van der Klaauw has recently updated its classic Ariadne. This delicious slice of Dutch (and Swiss) watchmaking combines the practicality of a chronograph with that of a complete calendar. A complete calendar indicates not only the date and the day of the week but also the month; it does need correcting for months with less than 31 days. In addition to that, the Ariadne also comes with a moon phase, and everything is nicely balanced in four evenly proportioned rings. The new Ariadne comes in three variants, silver, anthracite and blue, and, in addition, in two very special editions made for Dutch retailer Reijersen Juwelier. Worn on a leather strap, the new Ariadne retails for EUR 8,450.

Christiaan van der Klaauw Ariadne 2023 frosted dial

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Quick Facts – 40mm diameter – stainless steel case, polished – sapphire crystal front and back – onion-shaped crown – 30m water-resistant – frosted dial in silver, anthracite or blue – circular-brushed rings around the sub-dials – calibre CVDK7758 (Valjoux base), automatic – 48h power reserve – special rotor by Jochen Benzinger – hours, minutes, small seconds, complete calendar with date, day of the week, month, day/night indicator, moon phase and chronograph – leather strap with folding clasp – EUR 8,450

Annual Calendar – IWC Big Pilot’s Watches Annual Calendar Le Petit Prince

The next step up in calendar watchmaking is the annual calendar, represented here by the IWC Big Pilot’s Watch Annual Calendar Edition Le Petit Prince introduced last year. The annual calendar is a little bit more complex when compared to a complete calendar because it takes into account the length of months with 30 or 31 days. The only correction needed is the jump at the end of February. This IWC Big Pilot neatly arranges the indications for the date, day of the week and month in an arched window. The sunray-brushed blue dial follows the typical BP style. The in-house calibre 52850 is driven by a special rotor that depicts Le Petit Prince standing on his asteroid. It comes on a brown riveted leather strap, is limited to 250 pieces and retails for EUR 23,100.

IWC Big Pilot Annual Calendar Le Petit Prince IW502710

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Quick Facts – 46.2mm x 15.4mm – stainless steel case – oversized diamond-shape crown – sapphire crystal front and back – 60m water-resistant – blue sunray-brushed dial with white printed indices and markings – rhodium-plated hands with Super-LumiNova – arched window for annual calendar display – calibre 52850, in-house automatic with Pellaton winding system – 168h power reserve (7 days) – hours, minutes, small seconds, power reserve, annual calendar with date, day and month – brown leather strap – limited to 250 pieces – EUR 23,100

Perpetual Calendar – Patek Phillipe 5320G Perpetual Calendar Salmon

One of the most desirable complications in watchmaking is, without a doubt, the complex Perpetual Calendar. Most QPs indicate the time and a full calendar consisting of the day, date, weekday, month and leap year, but there are some other combinations as well. A perpetual calendar needs no monthly corrections and takes leap years into account as well. One of the finest recent specimens is this gorgeous Patek Philippe 5320G QP Salmon, set in a 40mm wide white gold case. The calibre 324 S Q indicates central hours, minutes and seconds. This is paired with a side-by-side weekday and month display and a moon phase and date sub-dial at the bottom. On the left side, there’s a day/night indication, with a leap year indicator on the right side. Worn on a brown alligator leather strap, the 5320G-011 costs EUR 84,700.

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Quick Facts – 40mm x 11.13mm – white gold case with stepped lugs – sapphire crystal on top – interchangeable solid white gold or sapphire crystal caseback – 30m water-resistant – rose gold-coloured opaline dial (salmon tone) – applied Arabic numerals and syringe-style hands in blackened gold – calibre 324 S Q, in-house automatic – 35-45h power reserve – hours, minutes, seconds, moon phases, QP with date, weekday, month leap year and day/night indicator – brown alligator leather strap with foldover clasp – EUR 84,700

Secular Calendar – Code 11.59 by Audemars Piguet Ultra-complication Universelle RD#4

The absolute rarest calendar watch complication is the secular calendar. This bypasses a peculiar element of the Gregorian calendar, which dictates that every four years is a leap year, except for years that are divisible by 100. However, if a year is divisible by 400, it counteracts the 100-year rule, and the year is again a leap year (I know, it’s complex). The first time this will occur is the year 2400, and only a handful of watches can adjust to these unusual leap- and non-leap years. That means a QP watch needs to be corrected every century, whereas a secular or semi-Gregorian calendar watch does not. The recently introduced Code 11.59 by Audemars Piguet Ultra-Complication Universelle RD#4 is one of those rare beasts, joining a tiny club that includes Svend Andersen and Frank Muller, to name just two.

The Code 11.59 Universelle is an absolute masterpiece, packing 40 functions and 23 complications (although debatable how that’s counted) into a single movement. It is accurate, with no need for adjustments to the calendar display until the year 2400. If you keep it running continuously, that is, which is a challenge in itself. In five windows spread across the closed or fully open dial, you can read the date, day of the week, month, year, astronomical moon and the phases of the moon. You might miss a leap year indication, but in fact, accurately displaying the full year every year is mechanically more complex. Combined with all the other indications and complications, the Universelle is an absolutely astounding piece. The price is astounding as well, at CHF 1,600,000.

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Quick Facts – 42mm x 15.5mm – 18k white or pink gold case with octagonal middle case – double-curved sapphire crystal – secret caseback opening onto the Supersonnerie sapphire membrane – 20m water-resistant – closed or open dials in black or beige – inner bezel with tachymeter scale – AP calibre 1000, in-house – automatic with semi-peripheral rotor – 1,140 components – 64h power reserve – grand & petite sonnerie, minute repeater, flying tourbillon, semi-Gregorian calendar (day, large date, month, year, astronomical moon, moon phases), flyback chronograph, split-seconds, hours and minutes – black alligator strap with gold folding clasp – additional black textured rubber-coated strap – CHF 1,600,000

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