Characterization of paper provides information vital to the preventive care and conservation of vast collections of paper-based materials in museums, libraries, archives and research repositories. Tracing papers, a relatively cheap material used abundantly by folk artists and architects, pose particular problems because of reactivity and instability inherent in their compositions and structures. Previous research published in MRS investigated the aging properties and the impact of conservation treatment on natural, prepared, vellum, and imitation vegetable parchment tracing papers [1, 2]. An additional group, that of genuine vegetable parchment papers, needs particular evaluation with respect to other tracing papers, since they are made by controversial production methods which while considered to be economically advantageous, are environmentally questionable. This technical study characterized three types of genuine vegetable parchment papers, assessing their relative degree of deterioration after aging and their reactivity to solvents commonly used with tracing papers to remove mounts and repairs. The parchment papers were compared optically (fiber, surface, and cross-section morphology; colorimetric, opacity, and gloss properties), chemically (FT-IR, SEM/EDS, and pH), and mechanically (tensile measurements) to provide baseline information on aging properties important to preventive care storage, and relative reactivity important to conservation treatment protocols. The effects of solvents used for conservation treatments (deionized water, ethanol, acetone, toluene, and ammonium hydroxide) were evaluated by comparing relative degrees of reaction (absorption).