Silverpoint is the art of drawing on a specially prepared surface with a pen of silver wire or even a silver spoon. A special ground made of bone, calcium carbonate, or marble dust mixed with gum arabic or rabbit skin glue is applied to a panel or sheet of paper as a drawing surface. This surface will have a tooth to it that will allow the silver wire to leave a mark and allows the artist to make very fine lines and details. This mark on the surface cannot be erased and will naturally tarnish to a warm dark grey/amber tone. Silverpoint is a traditional art form first used in the 14th & 15th centuries. Albrecht Durer, Hans Holbein, and Leonardo Da Vinci made many drawings using silverpoint.