Patina is the natural aging process that creates a distinctive surface layer on materials like metal, wood, or ceramics, often adding aesthetic depth and historical character to artworks. In art markets, patina can significantly enhance an artwork's value, providing evidence of authenticity, age, and preservation. Collectors and conservators carefully analyze patina as a crucial indicator of an artwork's provenance, materials, and historical significance. Too much patina can be considered damage and negatively affect price.