Gold leaf is a thin sheet of gold that has been hammered or rolled out to a very fine thickness, often less than 0.1 mm. It is used for gilding, which is the process of applying gold to surfaces to create a decorative effect. Gold leaf can be found in various applications, including art, architecture, and crafts. The application of gold leaf requires careful handling, as it is delicate and can easily tear. It is often applied using a special adhesive called gilding size and can be used on materials like wood, metal, and glass. Gold leaf adds a luxurious touch to objects and artworks.