A flat visual border separating a frame from the artwork within, made of cotton or alpha-cellulose paper.
Definition: A mat is a flat, usually paper-based border that surrounds and separates artwork from the frame. It serves both aesthetic and protective functions, providing visual depth, highlighting the artwork, and preventing direct contact with glazing or frame surfaces. Mats are typically made from archival-quality materials such as cotton rag, alpha-cellulose, or acid-free paper to ensure longevity and prevent deterioration of the artwork.
