Patina

Patina refers to the natural surface changes a painting or object acquires with age — the gentle ambering of oil varnish, the subtle softening of contrasts, and the mellowing of colour that collectors and connoisseurs have long associated with authenticity and history. Crucially, patina is distinct from grime: patina is a chemical transformation intrinsic to the materials themselves, while grime is accumulated surface dirt, nicotine residue, or degraded varnish sitting on top, which conservators can and do remove during cleaning. The distinction matters enormously in conservation ethics, since overzealous cleaning can strip away desirable, historically meaningful patina along with unwanted grime, and disputes over how much "the patina of age" should be preserved versus removed remain a live controversy in restoration practice today.