There are two possibilities - it's either a plain carbon print without a coating, or it's a carbon print with a glossy coating of collodion. If the former, then it's just called a carbon print, but if it's the latter, it is a chromotype. I think it's more probably the latter, even if it doesn't look particularly glossy (plain carbon prints are VERY matte!) just because this is a technique I know was used for personal photographs, whereas carbon prints were more usually used for reproducing photos of celebrities, art prints etc.
Chromotypes also always seem to have this thing where the frame of the photo, and the text underneath, looks like it's part of the photo...hope you understand what I'm trying to say here!
Carbon prints could be a variety of tones, and the colour is relatively permanent. Your is actually probably the colour that most "sepia" toned 19th century photos were to start with! Albumen prints (which most of them are) fade and yellow very rapidly.
Cheers
Prue
