"Crystoleum, "beauty Of North Africa" Painted Photograph Under Glass"
Crystoleum, Portrait of a North African woman circa 1890 signature top right Period frame in wood and gilded stucco. Image format: 10 x 12 cm Frame format: 22 x 25 cm Crystoleum is a painted photograph fixed under glass. An albumen print is glued to a concave glass, the paper support of the print is then rubbed, the remaining image is hand-colored with oil paint. This extremely expensive process was used for a short period from 1880 to 1910. https://www.lavalisearlesienne.com/product-page/crystoleum-beaut%C3%A9-d-afrique-du-nord-photographie-peinte-sous-verre 
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