Post-mortem ambrotype: standing father and seated mother cradling their dead child. Canada(?), circa 1860.

Sixth-plate ambrotype (wet collodion positive) with subtle hand tinting, 70 x 80 mm (sight); housed in an elliptical brass mount under cover glass, in a half leather case with embossed design featuring laurel wreath, flowers and both a Union Jack and French tricolour – suggesting a possible Canadian origin; the ambrotype is in very good condition.

The ambrotype – from the Greek ambrotos, “immortal” – is created using the wet plate collodion process developed by the English inventor Frederick Scott Archer, which came into vogue in Europe and North America from around 1854 as a cheaper alternative to the daguerreotype. A glass plate covered with a thin layer of collodion, then dipped in a silver nitrate solution, is exposed to the subject while still wet, then developed and fixed. When the reverse of this negative image is coated with a dark emulsion such as varnish or paint, the resulting image appears as a positive. The process requires the expertise and experience of a professional photographer. Every ambrotype is a unique image that can only be duplicated by copying with another camera.