Unconventional stones have thrilled watchmakers and jewellers since their discovery thousands of years ago, resulting in some truly avant-garde designs. Over the last century, pioneering jewellers like Grima have incorporated them into post-war pieces, shrewdly spotting the direction in which jewellery artistry was heading. He was also the first practitioner to feature jewellery by artists like Henry Moore and Picasso at his shows.

Now, this is a trend that has once again influenced fine watch making. Last year saw brands including Parmigiani and Piaget – who used both lapis lazuli and onyx in their Extremely Piaget double side cuff watch – looking back to the 1970s for inspiration, and embracing more unusual stones in the dials of their watches.

Hermès is the latest maison to have fallen for the romance of exotic gems, with the release of a new collection of miniature Faubourg ‘Pierre’ cocktail watches, which utilise lapis lazuli, onyx and malachite in their designs. Beautifully petite, the Faubourg watches were originally launched in 2014 as discreet and chic timepieces and the new models, while still delicately feminine, have been given an edge with striking dials in deep blues, inky blacks or intense greens.

Producing this plethora of peerless hues comes at a price, and the unique nature of the stones mean they come with their own challenges. In order to create something that is simultaneously beautiful and functional, the stones are subject to a rigorous selection process before they can be used on the dial. Only flawless examples are chosen to be cut and polished.

Malachite tends to be brittle, and so must be cut carefully in the right direction to avoid splintering. The hardness of onyx stops this being an issue, but polishing the stone is problematic, as it risks becoming grey or cloudy. Lapis lazuli has a more easy-going nature and is open to working on, but must strike the perfect balance, colour-wise, between azure and sea-blue in order to reach the distinctive tone that looks so striking when glimpsed on the wrist.