Ephesite
It is restricted to quartz-free, alumina rich mineral assemblages and has been found in South African deposits in the Postmasburg district as well as Ephesus, Turkey.In the case of ephesite the W compound is sodium and the (X,Y) is lithium and aluminium, it also bears two hydroxides as the end members.[5] Ephesite, a mica structure, arises from the stacking of T-O-T layers along the c-axis direction connected by I-cations where T,O, and I stand for tetrahedral-, octahedral-, and interlayer.Micas are determined and named for their end members and species that define a wide range of compositions.[8] The history of study of the mineral ephesite begins with its first appearance in Ephesus, Asia Minor at Gumach Dagh in a deposit also associated with emery discovered by J. Lawrence Smith in 1851.