The experts from the Book and Paper Conservation Centre of the Archives of the Republic of Slovenia used visual analysis to identify the type of a black-and-white photograph on glass from 1860 and to determine if it was made by inventor Janez Puhar (Johann Pucher). The photograph was embedded in the cover of the card, addressed to the Prince Bishop Jernej Vidmar, which is currently owned by the Archdiocesan Archives in Ljubljana. We investigated the photographers who at the time made photographs in the Slovenian territory, researched the methods used to produce the oldest photographs; then we examined the photograph with the naked eye and compared it at magnification to similar photographs from that time, and we examined all Puhar's photographs kept by the National Museum of Slovenia. The card was conserved and restored.