This paper deals with the documentation of the copy letters of the Schliemann archive belonging to the Gennadious Library, Athens, Greece. The goal of this paper is the proposition of a methodology based on the non destructive techniques for the documentation of the state ofpreservation and the study of different inks used in copy letters of the period from 1845 until 1890. A selection ofpages has been studied in ultraviolet reflection and fluorescence conditions and in the near infrared region of spectrum using infrared reflectography techniques in normal and macro mode both in recto and verso sides. Observations showed a wide variety of inks based mainly on their optical behaviour in different wavelengths, their oxidation condition and the quality of the copy.