Argyrotype is an iron-based silver printing process that produces brown images on plain paper. It is an alternative process derived from the argentotype, kallitype, and Van Dyke processes of the 19th century, but has greater simplicity, improved image stability, and longer sensitizer shelf-life. It was developed by Mike Ware. As with most alternative processes there is room for manipulating the process to achieve different effects, and since the image is produced on plain paper many drawing or print making processes can be combined with the original image.