Siliceous rocks are sedimentary rocks that have silica (SiO2) as the principal constituent. The most common siliceous rock is chert; other types include diatomite. They commonly form from silica-secreting organisms such as radiolarians, diatoms, or some types of sponges.[1]
References
- Schumann, Walter (1993). Handbook of Rocks, Minerals, and Gemstones. Houghton Mifflin Harcourt. ISBN 978-0395511374. Retrieved 2013-11-20.