Silicate

Silicates are a large class of minerals based on a tetrahedral silicon-oxygen unit (SiO4).

The spaceborne organism nicknamed "Junior", discovered by the USS Enterprise-D in 2367, had an outer shell made from silicates, actinides, and carbonaceous chondrite. (TNG: "Galaxy's Child")

The lifeforms on L-S VI are based on silicates rather than carbon. (DS9: "The Alternate")

In 2374, the mimetic USS Voyager collected silicates from a comet in the Podaris sector. (VOY: "Course: Oblivion")