Its green sapphire crystal marked a first in watchmaking when it was introduced on the Milgauss in 2007. Now this crystal is combined with an electric blue dial, an allusion to the emblematic lightning-boltshaped seconds hand and the watch’s technical purpose as a paramagnetic timepiece designed for engineers and scientists in the 1950s, a golden age of scientific research.
Milgauss was created in 1956 for engineers and technicians who are exposed in their work to magnetic fields which disrupt the performance of mechanical watches. It was designed to resist strong interference of up to 1,000 gauss, hence its name – “mille” being French for thousand – while maintaining its performance and precision as an officially certified chronometer.
Several innovations contribute to its resistance to magnetism. The first line of defence is a shield made of ferromagnetic alloys that surrounds the movement within the Oyster case, an invention patented by Rolex in 1954. The second line of defence involves two of the movement’s key components, the oscillator and the escapement, which are made of innovative paramagnetic materials developed by Rolex since the 2000s.
The 40 mm Oyster case of the Rolex Oyster Perpetual Milgauss is waterproof to a depth of 100 metres (330 feet). The characteristically shaped middle case is crafted from a solid block of particularly corrosion-resistant 904L steel. The fluted case back is hermetically screwed down with a special tool exclusive to Rolex watchmakers. The winding crown, fitted with the patented Twinlock double waterproofness system, screws down securely against the case.