Celluloid (sĕl′ū̇-loid), is a mixture of gun-cotton, camphor and various other substances. It is chiefly manufactured in the United States, most largely at Newark, N. J. Celluloid has many valuable properties. It is buff or pale brown in color, but it can be made as white as ivory or transparent. It can be molded or pressed into any form and turned, planed or carved. It is not affected by water or air. It can be hardened, and is then used for combs, piano keys and billiard balls. It can be colored to resemble amber or tortoise-shell. As an imitation of red coral, it is used in jewelry. Among the many articles made from it are knife-handles, buttons, napkin-rings, card-cases, thimbles, dolls, shirt fronts and collars.