copperas

English

Alternative forms

• coperas

Etymology

From Middle English coperas, coperose (“metallic sulfate”), from Old French coperose. Compare French couperose (“sulfate”), Medieval Latin cuprosa, Late Latin aqua cuprosa, Latin cupri rosa, "rose of copper".

Noun

copperas (usually uncountable, plural copperases)

1. iron(II) sulfate.
   • 1707, J[ohn] Mortimer, The Whole Art of Husbandry; or, The Way of Managing and Improving of Land. […], 2nd edition, London: […] J[ohn] H[umphreys] for H[enry] Mortlock […], and J[onathan] Robinson […], published 1708, →OCLC:

     It were superfluous to describe the Process of making the Aqua fortis; it shall suffice to let you know, that our common Coperas makes this Aquafortis well enough for our purpose […]

   • 1843 April, Thomas Carlyle, “ch. 6, Monk Samson”, in Past and Present, American edition, Boston, Mass.: Charles C[offin] Little and James Brown, published 1843, →OCLC, book II (The Ancient Monk):

     […] what a change has introduced itself everywhere into human affairs! How human affairs shall now circulate everywhere not healthy life-blood in them, but, as it were, a detestable copperas banker’s ink;

2. obsolete sulphate compound with one of three metals, zinc, copper or iron

Synonyms

• vitriol

Derived terms

• yellow copperas

Translations

iron(II) sulfate — see iron(II) sulfate

sulphate compound with one of three metals

• French: copperas ?
• German: Vitriol (de) n
• Italian: copparosa ?
• Spanish: capar rosa ?

Further reading

• copperas on merriam-webster.com
• David Barthelmy (1997–2023), “Copperas”, in Webmineral Mineralogy Database.
• “copperas”, in Mindat.org‎^[1], Hudson Institute of Mineralogy, 2000–2023.