Connellite

Connellite is a very rare mineral species, a hydrous copper chloro-sulfate, Cu₁₉Cl₄(SO₄)(OH)₃₂·3H₂O, crystallizing in the hexagonal system. It occurs as tufts of very delicate acicular crystals of a fine blue color, and is associated with other copper minerals of secondary origin, such as cuprite and malachite. Its occurrence in Cornwall was noted by Philip Rashleigh in 1802, and it was first examined chemically by Arthur Connell in 1847. Outside Cornwall it has been found only in Namaqualand in South Africa and at Bisbee, Arizona (USA)

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The type locality is Wheal Providence at Carbis Bay in Cornwall.^[1]

References

This article incorporates text from the Encyclopædia Britannica Eleventh Edition, a publication now in the public domain.