The bronze Rado Captain Cook is a watch that changes colour over time

When it comes to luxury Swiss watches, knowing you have something truly unique on your wrist can be a big deal – especially when that one-of-a-kind look changes gradually over time.

That’s exactly what the Captain Cook by Rado does, thanks to a bronze case that is plated with a very thin layer of gold.

Patination is the key here. Rado plates the case of the Captain Cook in a three-micron layer of gold. This protects the watch until it is sold, pausing the gradual ageing process buyers of bronze timepieces expect. Once it is bought and worn on a regular basis, the gold plating slowly disappears, revealing the bronze case below.

• Best watches
• 5 best watches to invest in right now
• Best watches under £1000
• Tudor Black Bay Navy Blue

This then begins to slowly age, developing a unique patina that varies depending on the wearer’s lifestyle, exposure to water, and the climate of where they live.

Over time, the bronze ages to form a unique patina, eventually making every example of the Rado Captain Cook look different.

Complementing the bronze 42mm case is a green sun ray dial and matching ceramic bezel, gold hour hands and hour markers, and a white date complication with red numerals at the three o’clock position.

The watch is completed by a box-shaped sapphire crystal, polished bronze screw-down crown, green leather strap with brushed bronze pin buckle, and a titanium case back.

The Rado Captain Cook is powered by an ETA C07 automatic mechanical movement with 25 jewels and an impressive power reserve of up to 80 hours. The watch is water resistant to 300 metres, but buyers are reminded that prolonged exposure to water can cause bronze to develop a greenish appearance, so it should be dried afterwards.