Yvan Arpa has put dust from the moon and rust from the Titanic in watches. This time, he has gone further by setting fossilised dinosaur excrement into his latest timepieces.
"I decided to take it a step further and use the forbidden material - coprolite," he told AFP, referring to the scientific name for fossilised faeces or droppings of ancient animals.
"By chance the colour inside is magnificent and it's 100 million years old, and it's the anti-material.
"People work with gold and silver, ... but I like to turn non-noble material into noble material," he added, speaking at Baselworld, the world's biggest watch and jewellery fair held in the northern Swiss city.
The price tag of 12,000 francs (8,365 euros, 11,265 dollars) for the watch, which looks rather rugged and comes with toad skin straps, is reasonable, according to Arpa, who noted that each is a "unique" work which contains a piece of history.
He said tests have shown that the excrement originated from a herbivore, and further investigations are ongoing for the exact dinosaur species.
Arpa, whose label Artya is based in the Geneva region of Vesenaz, explains his approach to watchmaking as one that is "very close to contemporary art."
"It's an industry where this approach is not done at all," he added.
Arpa, who cuts an odd dash in the precision minded Swiss watch industry, pointed out that he had created the first 'watch' which does not tell time.
That piece, which costs 300,000 francs, only tells day from night.
Among his latest collection are watches whose casing has been finished with "lightning strikes" or subjected to electric blasts of up to one million volts.
"It's to think differently," said the former mathematics teacher, who describes his work as the "dark side of watchmaking."
If Arpa works at deconstructing the traditional watchmaking world, his colleague Jean-Marie Schaller, who has also put dinosaur parts into his watches, takes a more traditional line.
Schaller, who runs the brand Louis Moinet in western Switzerland's Saint-Blaise, has also turned to rare materials to differentiate his creations from others in an industry dominated by long-established major players such as the Swatch Group or Richemont.
While other brands try to set their watches apart with the clearest diamond or rarest sapphire, Schaller has turned to bits of meteorites from Mars as well as the legendary Rosetta Stone meteorite - the oldest known rock in the solar system with an age of 4.56 billion years.
This year, Schaller has also come up with a limited edition that featured fragments of bones from a herbivore believed to be 150 million years old and which was found in western North America.
The dinosaur-bone watch retailing at 310,000 francs is accompanied by certification of the authenticity of the bones, said Schaller.
Unlike Arpa's creation, however, Schaller's sports the classic look of a fine mechanical watch complete with a "tourbillion" movement - a mechanism that helps counter gravity and thereby improve the watch's accuracy. Its bezel - the grooved rim - is also set with "baguette", or rectangular, diamonds.
"Our idea is to combine the art of watchmaking with special materials," he told AFP.
"We had the idea of using special meteorites as a travel through space series. Now we want to do the theme of travel through time," he added.