The colors are absolutely permanent and attain the virility and strength of nature so often lacking in hand colored work.
This photochrome print is part of “Views of People and Sites in Algeria” from the catalog of the Detroit Photographic Company.
And here, an image of the Betsy Ross house and then a detail of the color version produced with the Photochrom process.
The way the Photochrom process worked is somewhat of a mystery.
For hundreds of years, Algerian pirates maintained and secured the harbor against the naval powers of Europe. They obtained the exclusive rights to use the Swiss "Photochrom" process for converting black-and-white photographs into color images and printing them by photolithography.
When the French occupied Algeria in the 1830s, they made the harbor a center of commerce and naval power, and greatly expanded the port, which they used for both commercial and military purposes. This process permitted the mass production of color postcards, prints, and albums for sale to the American market.