Silicate
A silicate is a mineral built around silicon and oxygen, the main ingredient of rocky planets and stony meteorites.
Silicates are minerals whose basic building block is a tiny pyramid of one silicon atom surrounded by four oxygen atoms. These pyramids can stand alone, link into chains or sheets, or join into three-dimensional frameworks, and each arrangement gives a different mineral family.
Olivine has isolated pyramids, pyroxene has chains, clay minerals have sheets and feldspar and quartz have frameworks. Together, silicates make up most of Earth's crust and mantle and most of the Moon, Mars and the rocky asteroids. Stony meteorites are mostly silicates, which is why they can look surprisingly like Earth rocks.
In a meteorite description you will often see the word 'silicates' used for the stony part, as opposed to the metal and sulfide grains. In stony-iron meteorites such as pallasites and mesosiderites, the silicates are the olivine crystals or the pyroxene-feldspar rock mixed in with the metal.
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Level: Beginner Ages 7 and up