PVD stands for Physical Vapour Deposition. It is a modern method in which a microscopically thin layer of another material is applied in a vacuum chamber to the base material of the jewelry, most commonly surgical steel or titanium. This process is primarily used for coloring jewelry, for example, to achieve gold, rose gold, black, or blue hues. The resulting coating is very hard, abrasion-resistant, and corrosion-resistant, which ensures the jewelry retains its color long-term and is protected against scratching. PVD layers are also often hypoallergenic, meaning they are suitable even for people with sensitive skin.