Industrial mineral site no. 368, known as "Kittitas Diatomite Co". is a site in Kittitas County, Washington. This site has been associated with diatomite. A notation found in DGER Bulletin 37 on page 37 says "Two small pits expose 9 to 11 ft. of diatomite", and designates the value as "Recently operated by Kittitas Diatomite Co".