Audemars Piguet Royal Oak Ref. 4100BC - 'Midsize' W/ Tropical Diamond Dial

It’s not unfair to say that Audemars Piguet Royal Oak is one of the most iconic watches ever made. Designed in 1972 by Gerald Genta, the Royal Oak completely changed the way that we look at a steel sports watch. For the first time, stainless steel was treated as a precious metal - receiving complex finishing techniques of brushing, polishing, and beveling - all by hand. The idea that its eight hexagonal bezel screws would be finely finished and left exposed for the wearer to see was a revolutionary thought. It’s no surprise that the model became the calling card for the family owned Audemars Piguet - not to mention one of the most sought after watches in the world. While the initial 5402 was time-only, AP quickly began to capitalize on the success of the Royal Oak and begin to integrate other complications and variations into this case.

Which leads us to the Royal Oak that we have here, a 'midsize' Reference 4100BC. These pieces embody the ethos of the original Ref. 5402 'Jumbo' models, just in a slightly smaller and equally svelte 35mm case. In fact, at a glance, the only thing that differentiates it from its larger sibling, is the presence of a running central seconds hand.

This particular example, a Reference 4100BC from circa 1981, is something incredibly special and rare.

Firstly, rather than the usual stainless steel or yellow gold, this piece is crafter out of white gold — incredibly rare for any Royal Oak to begin with. Second, the dial within features not only factory applied diamond indices, but has also developed a mild 'tropical' patina from age. This is where the brass baseplate of the dial starts to show throughout the grey finishing on the 'micro-tapisserie' textured surface. The resulting patina is largely consistent and even and incredibly attractive. Being a non-luminous dial variant, the hands are a correct white gold 'pencil' set, also without luminous material. The case and matching integrated bracelet are in strong condition, having seen a light but tasteful previous polishing, and show just light signs of wear throughout. The clasp is the original white gold unit with an "AP" signed locking mechanism.

The 35mm size lends itself to, we think, a more comfortable wearing experience for more people, in fact, we'd say virtually any wrist, versus the way a full size 39mm Royal Oak which can fit a little odd on some wrists due to how flat it is. These watches strike the perfect balance between the size and value proposition that a Royal Oak can offer.

It is believed that the 4100BC shared its numbering with another rare gem-set reference, the 4153BC, totaling 40 units in total with just 20 units of each ever produced. This is a rare bird, full stop.