The Sapphire Crystal Is Now Used On Hublot Watches In More Ways Than One
Sapphire crystal has long established itself as the de facto crystal or “watch glass” for higher-end timepieces, owing to its virtual inability to be scratched. The lab-grown synthetic crystal is also rated nine out of 10 on the Mohs scale, which measures mineral hardness, meaning only material harder—such as a diamond—can scratch sapphire crystal.
While its benefits as a lens through which we look at the time have gone unchanged, the material has recently been brought to the forefront of the watchmaking world as the next big thing for case materials. A watch fully machined from sapphire crystal is still an uncommon sight in the watch world, and for good reason. The material is notoriously hard to work with, a trade-off for its scratch resistance and hardiness. In its crystalline form, sapphire crystal is extremely brittle, and the production process of even a flat piece is laborious. What more an entire case?
It is precisely this challenge that spurred Hublot to attempt working sapphire crystal into cases. Arguably the master of materials, the brand is renowned for its ability to weave new innovations into the production of its cases, from its own alloys such as Magic Gold and King Gold to other non-traditional materials, including carbon fibre and tantalum, and now sapphire.
In 2016, Hublot unveiled its first sapphire-cased watch, the Hublot Big Bang Unico Sapphire, quickly following up with several of its other watches encased in the same transparent material. Having obviously mastered the entire process of machining sapphire, Hublot upped the ante and showcased its finesse in materials the next year. Hublot unveiled an industry-first, venturing into uncharted territory: sapphire-cased timepieces but with colour—blue, pink, and even smoked black.
This year, Hublot added another colour to its list with the Spirit of Big Bang Yellow Sapphire. Like the previous coloured pieces, the art is in chemistry. Hublot fused sapphire crystalline with copper and aluminium oxide, giving the material its yellowish hue. The complexity of the process is all the more unbelievable up-close—the yellow sapphire is as clear as water, with no impurities to be observed. The multifaceted case of the Spirit of Big Bang, arguably more complex than that of the other watches, is also cause for admiration of the sapphire machination. Despite the material alchemy, the coloured sapphire’s physical properties are not altered. It remains one of the most scratch-resistant and hardest materials in the world.
The contrast of the dark grey openworked dial and movement against the lightness of the yellow sapphire is a modern, fun design, very much in line with the Hublot ethos. The yellow strap accompanying the watch is transparent as well and fitted with a titanium folding clasp. Limited to just 100 pieces worldwide, the Hublot Spirit of Big Bang Yellow Sapphire is equipped with the calibre HUB4700, a self-winding skeletonised chronograph movement with 50 hours of power reserve.
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