Arsenic and Old Bookcloth: Identification and Safer Use of Emerald Green Victorian-Era Cloth Case Bindings

ABSTRACT Analysis of nineteenth-century, cloth-case publishers’ bindings at Winterthur Library revealed starch-coated bookcloth colored with the toxic pigment “emerald green” (copper acetoarsenite). While this pigment was widely used in Victorian home goods and apparel, its use specifically in bookcloth has not been formally explored. A survey of bookcloth pigments was conducted to identify which toxic elements may be present in bookcloth and to determine how many bindings were colored with emerald green. English-language books at Winterthur published between 1837 and 1900 were analyzed with x-ray fluorescence spectroscopy. When arsenic and copper were found together, Raman spectroscopy was used to confirm emerald green. The dataset was further expanded using The Library Company of Philadelphia’s significant holdings of cloth-case publishers’ bindings. Copper and arsenic were detected in 38 rare and circulating books in total. Based on this data, trends in emerald green bookcloth use include: consistently vivid green hue; stamped decoration; English and American imprints from 1840s to 1860s. Quantitative analysis revealed significant levels of arsenic in friable bookcloth colorant. Emerald green books in the Winterthur collection were rehoused in zip-top polyethylene bags with hazard labels and circulating books were moved into the access-controlled rare book collection.