This is the first scratch-resistant gold and the hardest variety in the world, developed and patented by Hublot with the EPFL five years ago. Only diamond is capable of machining Hublot's 18-carat gold, certified by the Central Office for Precious Metals Control. It is the first scratch-resistant gold in the world and demonstrates a hardness of almost 1000 Vickers. Now produced in the high-tech foundry at the Nyon Manufacture, this patented material with magical properties was created by the revolutionary fusion of 24-carat gold and ceramic.
In the watch industry, it is usual for white, red and yellow gold to have a gold content of 75 percent or 18 carats. Copper and silver are added to the pure gold to obtain the various colours. Alloying gold with other materials changes its thickness, hardness and melting point, thus making it easier to work with.