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. It is isostructural with fehrite, which has magnesium in place of zinc, and gobelinite, which has cobalt in place of zinc.

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

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.