Purple crystal aggregates of the extremely rare mineral colinowensite (IMA2012-060) associated to majoritary blue effenbergerite from the type and only known locality worldwide in Wessels mine, Southafrica. Color is the basic distinctive way to differentiate colinowensite from effenbergerite since the first one is cleary purple and the second one is bright blue. This is difficult to see in the pictures, but it is easily seen with the specimen at hand. Named in honor of Colin R. Owen (1937 - 26 October 2020), a mineral dealer from Somerset West, South Africa. He provided the first specimens for study. Found in the Central-Eastern orebody of the Wessel's mine. — Photo: David Hospital · CC BY 4.0
Colinowensite
Colinowensite is an IMA-recognized mineral species in the silicate class, with the chemical formula BaCuSi₂O₆.
It crystallizes in the tetragonal crystal system (space group I4_1/acd).
Key properties: Mohs hardness 4; specific gravity 4.2; Purple streak; Vitreous luster; optically uniaxial.
IMA symbol Cwn, IMA status: approved, named in 2012.
Found in a hydrothermally-altered sedimentary manganese deposit.
It is found associated with Pectolite, quartz, aegirine, richterite, minerals of the garnet group, manganese and iron oxides with a dominance of hausmannite and hematite.
The mineral was named to honor Colin R. Owens (b. 1937), Somerset West, South Africa, who collected the first specimens.