- Saiph (stars.astro.illinois.edu)
SAIPH (Kappa Orionis). Orion’s magnificence stems from the striking figure that appears like the outline of a person looking back at you. But he – she to the Arabs – would be little without the brilliance of his stars.
- Siliceous rock (Wikipedia)
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.