Zussmanite [SEP] named after
Zussmanite
Zussmanite (K(Fe,Mg,Mn)[AlSiO](OH)) is a hydrated iron-rich silicate mineral. Zussmanite occurs as pale green crystals with perfect cleavage.
Discovery and occurrence.
It was first described in 1960 by Stuart Olof Agrell in the Laytonville quarry, Mendocino County, California. Zussmanite is named in honor of Jack Zussman (born 1924), Head of the University of Manchester’s Department of Geology and co-author of "Rock-Forming Minerals". 
In the Laytonville quarry, Zussmanite occurs in
minerals discovered in the Franciscan formation, Mendocino County, California. Deerite and howieite have been found at other locations while zussmanite has only been found at this type locality, making it a rare occurring mineral. Experiments have revealed that zussmanite is stable up to 600 °C at pressures between 10 kb and 30 kb and that the end members of zussmanite are orthoferrosilite, biotite and quartz. The example of the reaction is KFe[AlSi0](OH) (zussmanite) yields 10FeSiO (orthoferrosilite) + KFeSiAlO(OH) (biotite) + 4SiO