The ambrotype  (also known as a collodion positive) was the working man's Daguerreotype .  They were less expensive to produce, thus sell. I actually like them more than Daguerreotypes because they are more rare and I think have a more delicate look. They are often mistaken for Daguerreotypes.

It is actually an underexposed negative on a piece of glass, placed in a case over a black background (usually felt). Sometimes these can be found in very bad (visually) shape, and then carefully restored by taking apart the frame, & restoring the black material. They are often mistaken or misrepresented as Daguerreotypes.

The process involved taking collodion (a gelatin-like substance used to dress wounds) & mixing it with potassium iodide & coating a glass plate. Next the plate was immersed in silver nitrate, and while still wet, exposed in a camera. The image was then hardened & washed, & displayed in a case as described above. Very impressive images somewhat comparable to Daguerreotypes. The tintype process is similar to this process, except metal is used in place of glass.

Cases