Ktenasite, another mineral with∞2[(Cu,Zn)2(OH)3O]−octahedral sheets (original) (raw)

The crystal structure of ktenasite from Miniera Trentin (space group P2i/c, α = 5.589, b = 6.166, c = 23.751 Á, β = 95.55°) was determined by Patterson and Fourier methods and refined to a final R value of 0.058. The structure is characterized by corrugated sheets ^[(Cu.ZnMOHJaO]-of distorted copper-zinc polyhedra. Sulphate groups are connected to both sides of the octahedral sheet by corner sharing. The resultant composite tetrahedraloctahedral layers are connected each other by [Ζη(Η2θ)β] +2 octahedra through a system of hydrogen bonds. The crystal chemical formula for ktenasite from Miniera Trentin is Zn2(Cu5.2Zn2.8)(S04)4(0H)i2 • 12H20. The relations of ktenasite with other minerals are remarked and discussed.