Sudoite
A dioctahedral chlorite named for Japanese clay-science pioneer Toshio Sudo.
Intro adapted from Wikipedia (CC BY-SA).
Sudoite is an IMA-recognized mineral species in the silicate class, with the chemical formula Mg₂Al₃(Si₃Al)O₁₀(OH)₈.
It crystallizes in the monoclinic crystal system (space group C2/m). It is a member of the Chlorite, Clay structural group.
Key properties: specific gravity 2.63–2.68; optically biaxial.
IMA symbol Sud, IMA status: approved, named in 1962.
Disseminated in hematite ore, probably of hydrothermal origin (Negaunee, Michigan, USA); an authigenic mineral in aeolian sandstones (Kesselberg, Germany); in low-grade metamorphic assemblages (Ottr¶e, Belgium).
It is found associated with Hematite (Negaunee, Michigan, USA); quartz, carpholite, manganoan garnet, hematite (Biesenrode, Germany); pyrophyllite, diaspore, mica, bÄohmite (Itaya, Japan).
The name refers to Professor Toshio Sudo (1911{), University of Tokyo, Tokyo, Japan.