Any of the widely occurring compounds containing silicon, oxygen, and one or more matals with or without hydrogen .
the silicon and oxygen may combine with organic groups to form silicate esters.
Most rocks ( except limestone and dolomite ) and many mineral compounds are silicates are gemestone ( except diamond ) beryl, asbestos, talc, clays, feldspar, mica, etc.
Portland cement contains a high percentage of calcium silicates.
Best known of the synthetic ( soluble ) silicates is sodium silicate ( water glass ).