Why is a sandstone a metamorphic rock?

Metamorphic Rocks. Mineral information is presented here; Pictures of minerals are found at the bottom of the page. Marble is metamorphosed limestone or dolomite. ... Gneiss can be formed from a sedimentary rock such as sandstone or shale, or it can be formed from the metamorphism of the igneouse rock grantite. read more

Sandstone is a sedimentary rock, but it can be metamorphosed such as when in Quartzite. Metamorphosed means when the rock has undergone metamorphosis, but once sandstone has undergone metamorphosis, it is no longer sandstone. read more

Gneiss can be formed from a sedimentary rock such as sandstone or shale, or it can be formed from the metamorphism of the igneouse rock grantite. Gneiss can be used by man as paving and building stone. Quartzite is composed of sandstone that has been metamorphosed. Quartzite is much harder than the parent rock, sandstone. read more

No. Sandstone is sedimentary rock, where the individual grains of sand that compose the rock are visible without magnification. read more