Beato worked with collodion wet-plate glass negatives and albumen silver prints. Wet-plate negatives were in common usage from the early 1850s until the mid-1880s. Albumen prints, which used egg white as an emulsion on the paper, appeared around the same time but were widely used until around 1900.
Glass-plate negatives and albumen prints produce sharp, highly detailed photographs, as did the fact that they were contact prints, made by placing a negative directly on treated paper and exposing it.