Silica, or silicon dioxide (SiO2), is an oxide comprising one silicon atom and two oxygen atoms. Quartz is a type of silicon dioxide and silica are major components of sand. In 2267, Gothos was an iron-silica celestial body. (TOS: "The Squire of Gothos" ) In 2370, the emergent lifeform developing in the USS Enterprise-D cargo bay was made out of silica polymers, duranium and several unidentified compounds. (TNG: "Emergence" )