Wassonite is an extremely rare titaniumsulfide mineral with chemical formula TiS.[2][4] Its discovery was announced in a 2011 NASA press release as a single small grain within an enstatite chondritemeteorite called "Yamato 691", which was found during a 1969 Japanese expedition to Antarctica.[5] This grain represents the first observation in nature of the synthetic compound titanium(II) sulfide.
^Nakamura-Messenger, K., Clemett, S.J., Rubin, A., Choi, B.-G., Keller, L.P., Zhang, S., Rahman, Z. and Oikawa, K. (April 2011). "Wassonite, IMA 2010-074". CNMNC Newsletter (8): 293.{{cite journal}}: CS1 maint: multiple names: authors list (link)