Definition of green vitriol in English:

green vitriol

noun

mass nounarchaic
  • Crystalline ferrous sulphate.

    • ‘Much green vitriol was prepared at Deptford from ‘martial pyrites’ the common name then for IRON pyrites.’
    • ‘When the production of green vitriol was no longer convenient, the factory was closed and in 1872 demolished.’
    • ‘‘The source of the iron in medieval inks is green vitriol, an iron sulfate,’ Olin continues.’
    • ‘In a little while all the liquid had disappeared and there were left beautiful green crystals; sulphate of iron, or green vitriol, is the name of them.’
    • ‘The acids are extracted from the partially decomposed bark and, after drying for storage, are freshly mixed for use with wine and green vitriol.’