The tintype or ferrotype was invented by Fredrick Scott Archer in 1848 in London yet was patented by James Ambrose Cutting from Ohio in 1854.
The American opportunistic mentality made the tintype the first widely available and affordable photograph to the masses. While Europeans looked down upon the craft and hence few tintypes were made.
Making a tintype is a wet plate process, which requires a dark room to prepare and develop the image following the exposure. The plate is flowed with collodion, soaked in silver nitrate, loaded into a camera, exposed then taken back to the darkroom to be developed and washed before fixing.
Each tintype is a one of a kind direct positive that cannot be reproduced, which will last centuries with proper care following it being varnished.