The ambrotype was created by coating a glass plate with collodion and photosensitive silver nitrate. The plate was exposed in a camera, then quickly taken out and treated in a dark room with a developing solution to bring out the image. This produced a photographic negative which was then backed with something dark, such as dark felt or black varnish, which had the effect of inverting the image. It was then mounted and framed or cased, as had been the daguerreotype.
The ambrotype shown above is one from my own small collection. Unusually for Victorian portraits, both subjects are smiling, and she is grasping his hand quite firmly, which is what attracted me to it in the first instance. Unfortunately it has lost the frame or case in which it would have originally been mounted, but the the thin gilded, pressed metal, decorative frame is still present and in good condition. It shows the characteristic greyish appearance of an ambrotype - few of them have any of the lighter shades, and if you see lighter areas, it is wise to look for signs of touching up or that it may in fact be a cased tintype.
The three-quarter length portrait is of an unidentified seated couple, perhaps in their mid- to late 20s. I think they must be a recently married couple, because her wedding ring, earrings and the brooch at her neck, as well as his shirt buttons, have been highlighted with gold paint. It is interesting to note that the ring is on her left hand. As the ambrotype was a negative, the image would be reversed and ring should have been on her right hand. The photographer appears to have anticipated the problem, and perhaps instructed her to change the ring to the opposite hand and finger. As the enlarged and enhanced image below shows, however, she appears to also have a less prominent - and ungilded - ring on her "right" hand! The photographer's artist obviously took some liberties. The buttons on the gentleman's shirt and waistcoat give the game away, as they appear to be done up on the wrong side.
Typically for portraits from the mid- to late 1850s, they are seated side by side. This pose was not commonly used again in portraiture, except in the case of larger groups, and by some less experienced artists, until much later in the century. The woman's clothing (bell-shaped, layered and fringed sleeves, pleated bodice closed at the top with a gold brooch and trimmed with a lace collar, pointing downwards to a tightly corseted waist; a single full, ground-length skirt) and hair style (centrally parted, curved back down over the forehead to almost cover her ears, and drawn back to a bun on the back of her head) are indicative of the mid-1850s. The young man is wearing what appears to be a frock coat, simple dark waistcoat, and shirt with a turned over collar and rather untidily knotted bowtie. He has a slight Quaker-style chin-beard, with only a suggestion of a moustache, and hair parted on his "left"(right)-hand side.
I estimate that this was quite an early ambrotype, and probably dates from between 1854 and 1857. Nobody looks quite the same in the mirror - in other words, nobody has an absolutely symmetrical face. For the first time in a century and a half, we can now view the photo as it might have been printed more accurately, had the technology been available at the time.
Dating Family Photos 1850-1920, by Lenore Frost, self publ. 1991, Essendon, Victoria, Australia.
Family Photographs 1860-1945, by Robert Pols, publ. 2002 by Public Record Office, London, England.