The Chalcanthite mineral is a water-soluble copper hydrated sulphate, formed by sulphide oxidation, always in arid regions. Besides the intense color, that helps a lot in its identification, Chalcanthite has a very stressed flavor: it is extremely bitter and astringent. Simply touch the mineral with the tip of the tongue and feel - for a long time - the unpleasant flavor it has.
This image was found in New Mexico (USA). Chalcanthite is also found in Chuquicamata and in other arid places in Chile.
Its name comes from the Greek ‘Khalkos’, meaning ‘copper’ and ‘anthos’, meaning ‘flower’, as it used to be called ‘copper flower’ in the past. It is also popularly known as vitriol blue and cupric sulphate.
It is produced synthetically, for usage in viticulture (grape production), in pest control; to treat swimming pools as fungicide, and also as blue color pigment. Chalcanthite photo credit: Henry Yu
Source: MM Gerdau - Museu das Minas e do Metal -