Example?
Colour images (whether film, plate or printed) did not become available for the absolute vast majority of consumers until the late 1800s / early 1900s. However, the process of hand colouring images was certainly possible and very prevalent - especially among the public. Typically, a small amount of pigment was layered onto the surface of an image and then sealed with varnish to produce the 'colour' image. I'd like to see an example though of what you think you're suggesting.