This article offers a reflective look at two interdisciplinary research projects mixing history and physical chemistry, one dealing with the analysis of inks used in the scribal offices of Chartres during the second half of the 14th century, the other studying the composition of the parchment used in making charters and medieval manuscripts at the Cistercian abbey of Orval. The article highlights how the form and content of our interdisciplinary work are closely dependent on the objects studied. We offer an exploration of this, by way of comparing how writing materials are described and presented in the medieval written sources with the data resulting from laboratory analyses.