verdigris

Verdigris reacts with binding media and forms transparent glazes (copper resinates).

Manufacturer / product code:  Kremer / 44450
Chemical description: basic copper-(II)-acetate-1-hydrate. Kremer PDF 
Color: green
Color Index: PG20
More info: Pigments Through The Ages  Colourlex

Verdigris is one of the oldest synthetic pigments in the history of art, known for its vivid blue-green hue and distinctive translucent quality. Its name derives from the Old French vert-de-Grèce (“green of Greece”), reflecting its geographical association. Produced by exposing copper plates to acetic acid vapors—traditionally wine or vinegar—the pigment is essentially a family of copper acetates. Recipes for its manufacture appear as early as antiquity, including in Pliny the Elder’s Naturalis Historia, and the process remained largely unchanged well into the early modern era.

Verdigris was widely used throughout the Middle Ages, both in manuscripts and panel painting. Illuminators prized it for its brilliance and its ability to create delicate, luminous greens in foliage, drapery, and ornamental details. In panel and fresco painting, artists used verdigris to achieve intense greens that were difficult to obtain from mineral-based pigments such as malachite or green earth. During the Renaissance, its popularity persisted, appearing in the works of masters including Giotto and later Venetian painters, who valued its transparency for glazing techniques.

However, verdigris has always presented challenges. It is chemically unstable, prone to darkening, browning, or even completely losing its color when exposed to humidity, sulfur compounds, or certain binders. Despite these limitations, its striking chromatic intensity ensured its continued use until more stable synthetic greens became available in the 18th and 19th centuries.

Raman Spectroscopy 532 nm – ElviRa Spectrometer for Art

Reflectance spectroscopy – Gorgias Spectrometer for Art

NIR Reflectance spectroscopy

FT-IR Spectroscopy (Non-invasive Diffuse Reflectance Probe)