Ktenasite

Ktenasite
Ktenasite
	Ktenasite. Locality: Maria Josefa Mine, Rodalquilar, Níjar, Almería, Andalusia, Spain. Picture width 1 mm. Collection and photograph Christian Rewitzer
General
Category	Mineral sulphate
Formula	ZnCu4(SO4)2(OH)6·6H2O
IMA symbol	Kte
Strunz classification	7.DD.20
Dana classification	31.6.3.1
Crystal system	monoclinic
Crystal class	2/m-Prismatic
Identification
Color	blue-green to emerald green
Mohs scale hardness	2 to 2.5
Luster	vitreous
Density	2.94 to 2.97 g/cm3
Refractive index	1.57,1.61,1.62
Birefringence	0.049-0.054
2V angle	51o to 59o

Ktenasite is a rare hydrous zinc copper sulphate mineral, with the formula ZnCu₄(SO₄)₂(OH)₆·6H₂O.^[1] It is isostructural with fehrite, which has magnesium in place of zinc, and gobelinite, which has cobalt in place of zinc.^[2]

Ktenasite was named for Greek geologist and mineralogist Konstantinos Ktenas by his colleague, P. Kokkoros, who first described the mineral in 1950.^[1]^[3] Ktenasite was initially found in the Lavrion mining district, near Athens, Greece ^[4] and is now known from multiple localities^[5]^[6] where it often forms by secondary alteration of pre-existing sulphide minerals such as chalcopyrite and sphalerite.^[1]

References

1 2 3 "Ktenasite". Retrieved 17 October 2026 – via Mindat.org.
↑ Mills, S. J.; Kolitsch, U.; Favreau, G.; Birch, W. D.; Galea-Clolus, V.; Henrich, J. M (2020). "Gobelinite, the Co analogue of ktenasite from Cap Garonne, France, and Eisenzecher Zug, Germany". Eur. J. Mineral. 32 (6): 637–644. Bibcode:2020EJMin..32..637M. doi:10.5194/ejm-32-637-2020.
↑ Kokkoros, P (1950). "Ktenasit, ein Zink-Kupfersulfat aus Lavrion (Griechenland) (in German)". Tschermaks Mineral. Petrogr. Mitt. 1: 342–346. doi:10.1007/BF01145389.
↑ Τζεφέρης, Πέτρος (11 September 2022). "Type Locality Minerals from the Lavrion Mining District". Ελληνικός Ορυκτός Πλούτος. Retrieved 17 October 2026 – via oryktosploutos.net.
↑ Raade, G; Elliott, C. J; Fejer, E. E. (1977). "New data on ktenasite". Mineralogical Magazine. 41 (317): 65–70. Bibcode:1977MinM...41...65R. doi:10.1180/minmag.1977.041.317.10.
↑ Mellini, M; Merlino, S (1978). "Ktenasite, another mineral with ∞²[(Cu,Zn)₂(OH)₃O]−octahedral sheets". Zeitschrift für Kristallographie. 147 (1–2): 129–140. doi:10.1524/zkri.1978.147.1-2.129.

[Mindat-1] 1 2 3 "Ktenasite". Retrieved 17 October 2026 – via Mindat.org.

[2] Mills, S. J.; Kolitsch, U.; Favreau, G.; Birch, W. D.; Galea-Clolus, V.; Henrich, J. M (2020). "Gobelinite, the Co analogue of ktenasite from Cap Garonne, France, and Eisenzecher Zug, Germany". Eur. J. Mineral. 32 (6): 637–644. Bibcode:2020EJMin..32..637M. doi:10.5194/ejm-32-637-2020.

[3] Kokkoros, P (1950). "Ktenasit, ein Zink-Kupfersulfat aus Lavrion (Griechenland) (in German)". Tschermaks Mineral. Petrogr. Mitt. 1: 342–346. doi:10.1007/BF01145389.

[Lavrion-4] Τζεφέρης, Πέτρος (11 September 2022). "Type Locality Minerals from the Lavrion Mining District". Ελληνικός Ορυκτός Πλούτος. Retrieved 17 October 2026 – via oryktosploutos.net.

[5] Raade, G; Elliott, C. J; Fejer, E. E. (1977). "New data on ktenasite". Mineralogical Magazine. 41 (317): 65–70. Bibcode:1977MinM...41...65R. doi:10.1180/minmag.1977.041.317.10.

[6] Mellini, M; Merlino, S (1978). "Ktenasite, another mineral with ∞²[(Cu,Zn)₂(OH)₃O]−octahedral sheets". Zeitschrift für Kristallographie. 147 (1–2): 129–140. doi:10.1524/zkri.1978.147.1-2.129.

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