Among chronograph watches, the Patek Philippe 5070 occupies the summit of Olympus. Originally launched at Basel in 1998, this 42mm mechanical monster quickly built a reputation as the ultimate power watch for collectors with the taste and the budget required to put it on their wrists. And the Patek Philippe 5070P -- in platinum -- is the ultimate version of the ultimate chronograph. Rare, beautiful, valuable, and vaunted, this is what you buy when the platinum Rolex Day Date loses its luster.

The 1998 Patek Philippe 5070J in yellow gold established the format for the entire series. Its 42m diameter was ambitious in an era when even large men's watches still measured under 40mm. Patek Philippe's own Calatrava dress watches typically measured 33-37mm during the late 1990s, so the 5070 chronograph was closer in size to a Panerai Luminor than to any series production Patek Philippe watch. More than a new chronograph, the 5070 was the true successor to the celebrated Patek Philippe 1463 that ended its run in the late 1960s.

The prototype Patek Philippe 2512 split seconds chronograph of the 1950s inspired the dial and case designs of the 5070. Its Lemania-based caliber CH 27-70 was dwarfed by the case, and Patek Philippe designers used a series of visual tricks to disguise this disparity on the dial side. Traditional Geneva watch finish blazed in glory under this timepiece's sapphire display caseback.

A white gold 5070G arrived in 2002, and the rose gold 5070R replaced the "G" in 2004. But it was the 2008 debut of the platinum 5070P that served as a sensational sendoff to a glorious production run. The 5070P was produced in fewer than 250 pieces over two model years spanning 2008 and 2009, and it was an investment-grade collectible from the beginning. The blue metallic sunburst dial is exclusive to this model, and it contrasts in icy fashion against the blindingly white platinum case. Because this is a platinum watch from Patek, a brilliant cut diamond sits between the lugs at six o'clock.

As with all 5070s, the platinum model includes a broad stepped bezel designed to disguise the disparity between the size of the 42mm case and the 27mm movement. A sunburst metallic blue dial includes a tachymeter scale among several concentric circles that populate the face of this watch. In traditional fashion, the chronograph is a twin-register design, and the enormous chronograph seconds hand chugs in lurching leaps at a pocket watch-like 18,000 vibrations per hour.

Patek caliber CH 27-70 is based on the Lemania 2310 manual wind ebauche. This movement, which has roots in the early 1940s, is a traditional manual-wind chronograph with lateral clutch and column wheel. From that baseline, Patek Philippe adds immense proprietary refinements. The power reserve increases from 48 hours to 60 hours; a free sprung Gyromax balance replaces the mobile stud adjustment of the Lemania; an overcoil hairspring replaces the Lemania's flat spiral; Patek's 27-70 is adjusted by hand in six positions and at two different temperatures in order to ensure chronometric excellent. Finally, Patek watchmakers drastically upgrade, decorate, and outright replace Lemania hardware in order to justify stamping this caliber with the hallowed Geneva Seal.

The market price of a Patek Philippe 5070P ranges from $220,000 to $320,000 depending on the condition, provenance, and boxed set accessories included with the example. In contrast, all of the standard gold models of 5070 chronograph can be purchased for under $100,000. As a note to collectors, recall that a London Exhibition 5070P-013 in platinum was created as a special edition for the UK market. The likely production count of these is five pieces, and those examples stand in a price class by themselves.