blue vitriol

American  

noun

Chemistry, Mineralogy.

1. a salt, copper sulfate, CuSO 4 ⋅5H 2 O, occurring naturally as large transparent, deep-blue triclinic crystals, appearing in its anhydrous state as a white powder: used chiefly as a mordant, insecticide, fungicide, and in engraving.

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blue vitriol British  

noun

1. the fully hydrated blue crystalline form of copper sulphate

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blue vitriol Scientific  

1. A blue, crystalline compound of copper sulfate. Blue vitriol is soluble in water, and is a very important industrial salt of copper. It is used in insecticides and germicides, in electrolytes for batteries, and in electroplating baths. Chemical formula: CuSO ₄ ·5H ₂ O.

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Etymology

Origin of blue vitriol

First recorded in 1760–70

Example Sentences

A little solution of blue vitriol, or a little spirits of turpentine—either followed by a coating of warm tar—promptly cures it.

From Project Gutenberg

Vitriol, vit′ri-ol, n. the popular name of sulphuric acid: a soluble sulphate of a metal—green vitriol=sulphate of iron, blue vitriol=sulphate of copper, white vitriol=sulphate of zinc.—v.t.

From Project Gutenberg

While Pliny gives prominence to blue vitriol, his solution for colouring leather must have been the iron sulphate.

From Project Gutenberg

In the Daniell cell the zinc plate is in dilute sulphuric acid, and the copper plate is in a solution of blue vitriol or copper sulphate.

From Project Gutenberg

A single grain of sulphate of copper, or blue vitriol, will communicate a fine azure tint to five gallons of water.

From Project Gutenberg