The thesis addresses the issue of metal jewellery in Titanium, Niobium, Tantalum and Zirconium, focusing on modifying the semi-precious metal surface properties and analyse the interference colors as consequence of anodic oxidation treatments for the jewellery industry. The semi-precious jewels are subjected to long-lasting conditions: they can lose original lustre becomingopaque, staining and scratching and some parts can be worn out by skin contact, or by di!erent surfaces or scraping agents. To take care of jewellery is essential to avoid collisions, but the total surface control makes an utopia to achieve during the daily routine. The aim of the research is to investigate experimentally the wear mode, identifying the best metal with minimum variation level of the oxide layer and surface morphology. The tests examine the fatigue surface wear, the corrosion and the sliding wear, simulating the conditions in which a precious may suer.