Feral Alphabets: I

From: In Relief

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n ancient times, verdigris was used as a pigment, and pieces of copper were exposed deliberately to acetic acid, or vinegar, to obtain it.  Verdigris—the greenish patina that forms naturally when copper, brass or bronze are exposed to the weather—can be one of several chemical compounds depending on the exposure which caused it. In the case of acetic acid, it is copper acetate which forms, and green pigments of this sort were used by painters up to the 19th century, when other more stable (and less toxic) sources became available.

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