The Fondation Marcello holds a significant archive consisting of letters and other material pertaining to the artistís life and work. This includes correspondence with numerous individuals from within the artistic, political and aristocratic circles frequented by the duchesse Colonna, and with members of her own family (and her mother in particular). The core holdings (ca. 2,000 letters) are presently held by the Archives de líEtat de Fribourg and have been catalogued and scanned for greater ease of access. The catalogue can be accessed on line. Consulting the archive material requires the authorisation of the Fondation Marcello which can be requested by contacting ArchivesEtat@fr.ch.