verdigris(redirected from Verdigrease)
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verdigris(vûr`dəgrēs'), one of three copper acetates: blue verdigris, Cu(CH3COO)2·CuO·6H2O; green verdigris, 2Cu(CH3COO)2·CuO·6H2O; or neutral verdigris, Cu(CH3COO)2·H2O; or a mixture of them. It is a poisonous gray-green to green-blue substance that is formed by the action of acetic acid on copper or copper oxide, e.g., verdigris can form on copper pots used to cook acidic foods such as tomatoes. Verdigris is used as a mordant in dyeing, as a pigment, and in making Paris greenParis green,
also called Schweinfurt green, an extremely poisonous, bright green powder that was formerly used extensively as a pigment (e.g., in wallpaper) and that is sometimes used as an insecticide or to kill plant fungi; it must be used with great caution because of its
..... Click the link for more information. . Verdigris may also be used to mean patinapatina
, coating of carbonate of copper on articles of copper or bronze, formed after long exposure to a moist atmosphere or burial in the earth. Although commonly green, patina varies in color and consistency; it may be red, brown, black, blue, or gray, or it may be smooth,
..... Click the link for more information. .
The green copper carbonate formed on copper roofs and statues that are exposed to the atmosphere; the patina it produces can be carefully controlled.
The greenish blue corrosion on copper that has been exposed to air for a long period of time; used as a pigment.
1. a green or bluish patina formed on copper, brass, or bronze and consisting of a basic salt of copper containing both copper oxide and a copper salt
2. a green or blue crystalline substance obtained by the action of acetic acid on copper and used as a fungicide and pigment; basic copper acetate