Writer Giorgia Mondani spotted wearing a Rolex

Giorgia Mondani, the Italian horologist, author, and publisher behind the definitive Rolex reference books, was recently spotted wearing a Rolex Cosmograph Daytona 'Zenith' reference 16528 in 18K yellow gold with a black dial — a watch that speaks directly to her encyclopedic expertise in the marque.

The reference 16528 entered production in 1988 as part of Rolex's broader refresh of the Daytona line, replacing the manually wound ref. 16528's predecessor and introducing automatic winding to the gold Daytona for the first time. The movement inside is the caliber 4030, a heavily modified version of the Zenith El Primero — itself one of the first automatic chronograph movements ever produced. Rolex reworked the El Primero extensively, reducing the beat rate from 36,000 vph to 28,800 vph and replacing numerous components to meet their own tolerances, though the Zenith architecture underneath remained. The black dial variant is among the most legible and visually striking configurations of the reference, with its contrasting sub-registers and bold case presence in 18K yellow gold.

For collectors, the 'Zenith' Daytonas — spanning references 16520 in stainless steel and 16528 in yellow gold — occupy a canonical position in the hobby. Produced until 2000, when Rolex transitioned to the in-house caliber 4130, these are the last Daytonas to use an externally sourced movement. Early examples with the original El Primero-based caliber command particular attention, and the yellow gold 16528 remains rarer in absolute production numbers than its steel sibling.

Mondani is not merely a celebrity wearing a fine watch — she is arguably the world's most published authority on Rolex, having authored the multi-volume Rolex Encyclopedia series. Her choice of a vintage Zenith Daytona in yellow gold is entirely consistent with a collector who has spent decades cataloguing exactly these references. It is a working tool as much as a personal statement.

On the current market, the Rolex Cosmograph Daytona Zenith ref. 16528 in yellow gold with a black dial trades in the $30,000–$40,000 range depending on condition, originality of the dial, and completeness of the set. It represents strong value relative to its historical significance within the Daytona lineage.