Use 4 ml per 8x10 print. Dry the paper before proceeding. Exposure Contact print in sunlight. The exposure is complete when the image is about twice as dark as you would like the finished print. Wash the print for 20-30 minutes.
Air dry the print.
Toning Prints from this process may be toned as you would any silver gelatin prints. Gold toner would have been used during the period when this process was popular. Gum Bichromate Can also be referred to as Gum Dichromate or Pigmented Gum printing. One of the earliest printing processes. Gum prints can be made in any color using water soluble pigments.