[Seated woman]

Rare c.19th cased sixth plate ambrotype of a seated woman wearing in a black dress with her earings, ring and a brooch highlighted in gold. The cased is in embossed leather and the ambrotype is set within an oval ormolu engraved surround with thin gilt slip.

The invention of wet collodion photography processes in the 1850s allowed the development of two new kinds of photographs; ambrotypes and tintypes. These new formats shared many characteristics with the earlier daguerreotypes but were quicker and cheaper to produce. Primarily used for portraiture, each photo is a unique camera-exposed image.

James Ambrose Cutting patented the ambrotype process in 1854. Ambrotypes were most popular in the mid-1850s to mid-1860s. Cartes de visite and other paper print photographs, easily available in multiple copies, replaced them.  An ambrotype is comprised of an underexposed glass negative placed against a dark background. The dark backing material creates a positive image. Photographers often applied pigments to the surface of the plate to add color, often tinting cheeks and lips red and adding gold highlights to jewelry, buttons, and belt buckles. Ambrotypes were sold in either cases or ornate frames to provide an attractive product and also to protect the negative with a cover glass and brass mat.

They were as available in the following standard-sizes. The most common size was the sixth plate.
Imperial or Mammoth Plate – Larger than 6.5 x 8.5 inches
Whole Plate – 6.5 x 8.5 inches
Half Plate – 4.25 x 5.5 inches
Quarter Plate – 3.25 x 4.25 inches
Sixth Plate – 2.75 x 3.25 inches
Ninth Plate – 2 x 2.5 inches
Sixteenth Plate – 1.5 x 1.75 inches