The daguerreotype is an extraordinary photographic medium. It came about through a partnership between the genius inventor Nicéphore Niépce (later his son Isidore) and the French showman Louis Daguerre. It was the very first publicly announced method of photography.
The process of daguerreotypy firstly requires a highly polished sheet of silvered copper to be sensitised with the fumes of with iodine and bromine. The plate is then exposed in-camera and developed with mercury fumes. Permanence is given to the image by first fixing it with sodium thiosulphate and then gilding it by heating the plate whilst its surface is supporting a solution of gold chloride.
Daguerreotypes are unique in that they cross the boundaries of time and space. The highlights are created at the time of the making whilst the shadows are dependant on ambient light when viewing the image.
The finished artefact is often lovingly referred to as an 'image object' rather than a photograph as each daguerreotype is a one-of-a-kind entity.