Hublot continues to push the envelope when it comes to the materials it uses in its watch cases. After introducing the Big Bang Unico Sapphire, the first large-scale-production watch with a case made of transparent sapphire, last year, the brand doubled down on sapphire at Baselworld 2017, using it as a case material for the first time in its tonneau-shaped Spirit of Big Bang series, and introducing two colorful new Big Bang Unico models with red- and blue-tinted sapphire cases ? the latter representing the very first time blue sapphire has been used in horology.
 
Hublot Spirit of Big Bang Sapphire
Like its predecessors in titanium, King gold and ceramic case, the Hublot Spirit of Big Bang Sapphire has a barrel shaped case measuring 45 mm wide and 15.10 mm thick. Hublot used four blocks of machined sapphire to create this transparent version of the case ? a very difficult process made all the more challenging by the unusual shape; according to the company, new machines and new processes to polish and finish components needed to be developed. The resulting case, after almost 100 hours of work involving 3D machining, is one that is as hard and nearly as scratch-resistant as diamond (sapphire is 9 on the Mohs hardness scale; diamond is 10), whose crystal clear design offers an unimpeded view of the skeletonized, self-winding movement, Caliber HUB4700. Based on the famous El Primero from Zenith, Hublot’s sister brand within the LVMH luxury group, the movement h...