Characterization of Filamentous Accretions On Daguerreotype Surfaces

Abstract

Daguerreotypes were a popular method of photography since their introduction in 1839 until their eventual demise ca. 1860. A silver mercury amalgam deposited on a polished silver surface captured many unique images of individuals, landscapes, and the natural world. Daguerreotypes that have survived to the present day exhibit many unique patterns of deterioration and are susceptible to damage. The appearance of fibril accretions on improperly stored daguerreotypes is a common symptom of deterioration. Initial investigations based on morphologic observations of these fibrils concluded that the structures were fungi encrusted with silicon and smaller amounts of other chemicals. Later work proposed that these accretions were strictly chemical in nature. Gross microscopic observation of the fibrous accretions present on several daguerreotypes examined at Harvard University suggested that these structures were fungal in origin. This study used traditional culture techniques and nonculture molecular methods to isolate viable fungal organisms from the face of a daguerreotype and detect fungal nucleic acids. Additional microscopic and energy-dispersive x-ray spectroscopy analyses were performed to further characterize the fibrous accretions. The data demonstrates that some fibril accretions are due to fungal contamination of the daguerreotype surface.