Rolex Explorer II 16570 ‘Chicchi di Mais’ - Strong Patina Dial - Original Punched Warranty

In 1971, Rolex reimagined the Explorer, first introduced in 1953, as a more function-driven tool watch with the debut of the Explorer II. Rather than replacing the original model, the Explorer II was introduced as a parallel line. The ‘II’ designation would later become standard for modernized versions of other Rolex models, such as the GMT-Master II introduced in 1982.

The inaugural Explorer II, reference 1655, nicknamed the ‘Freccione’, embraced a bold 1970s aesthetic, featuring a distinctive black dial and a prominent orange 24-hour hand. Visually, it bore little resemblance to the Explorer II we know today.

Bridging that stylistic gap was reference 16550, produced for just four years starting in 1985. It introduced a dial design more in line with Rolex’s professional series and, for the first time, offered both black and white dial variants. This transitional and short-lived reference was succeeded by the longer-running 16570, which production ran until 2011.

This new reference features the upgraded Caliber 3185, which replaced the 3085 with a longer 50-hour power reserve and a slimmer profile, reduced from 7.20 mm to 6.45 mm. In 2007, near the end of the model’s run, it was further updated with the Caliber 3186.

Over the course of the reference’s evolution, various luminous materials were used. In the earliest examples, produced from approximately 1989 to 1997, tritium was employed, as indicated by the ‘SWISS-T<25’ marking at 6 o’clock.

The present example, dating to 1991, belongs to this early generation. What makes it particularly special is the way the tritium has aged over time, developing a rich, warm yellow patina on both the hands and indices. This rare and highly desirable transformation, seen in only a small number of reference 16570s, is affectionately known among collectors as ‘Chicchi di Mais’, Italian for ‘corn kernels’ and lends the watch a striking visual presence and undeniable charm.

Preserved in very good condition, the watch is accompanied by its original Rolex punched warranty, confirming its initial sale in 1991 by the renowned Milanese retailer Pisa.