Chalcanthite

Chalcanthite Group. Copper analogue of siderotil and pentahydrite. Chalcanthite is natural, water-soluble copper sulphate pentahydrate. It is a secondary mineral that is formed in arid climates or in rapidly oxidizing copper deposits. It is usually of post-mining formation, forming on mine walls and by the action of acidic surface waters on veins of copper ore. CAUTION: Many, usually well-crystallised chalcanthite specimens offered for sale (e.g. on-line auctions), are artificially grown.

History

Activities related to discovery and approval of the group members

Structural context

Chalcanthite
Crystal System triclinicCrystal Class pinacoidalSpace Group P-1
a6.11—6.141 (6.1249)
b10.41—10.736 (10.682)
c5.957—5.986 (5.9704)
alpha82.27—82.376 (82.3169)
beta107.28—107.43 (107.369)
gamma102.593—102.67 (102.6376)
volume352.135—366.361 (362.8025)

Based on 8 measurements

Chemical context

Stoichiometric formulas

Chalcanthite
mindat.org
  • March 13, 2023CuSO4·5H2O
IMA
  • March 13, 2023Cu(SO4) · 5H2O
mineralogy.rocks
  • Aug. 30, 2022Cu2+S6+O4·5H2O

Elements recorded on EPMA

7
Cu
7
O
7
S
4
H
2
D

Physical properties

ColorColor entities, recognized using a custom trained NER model
    • green blue
    • light blue
    • dark blue
    • pale blue
    • colourless
    Color noteOriginal color note from the source
    Green, green blue, light blue, or dark blue; colourless to pale blue in transmitted light.
    StreakStreak entities, recognized using a custom trained NER model
      Streak noteOriginal streak note from the source
      White
      Lustre
      Vitreous
      Resinous
      Fracture
      Conchoidal
      Transparency
      Transparent
      Translucent
      Luminescence
      None
      Tenacity
      brittle
      Hardness
      2.5
      Calculated density
      2.282