Know all about Marl and Siltstone properties here. All properties of rocks are important as they define the type of rock and its application. Marl and Siltstone belong to Sedimentary Rocks.Texture of Marl is Earthy whereas that of Siltstone is Clastic. Marl appears Rough and Dull and Siltstone appears Rough. The luster of Marl and Siltstone is dull. Marl is available in beige, brown, green, grey, white colors whereas Siltstone is available in brown, red, reddish brown colors. The commercial uses of Marl are creating artwork, soil conditioner and that of Siltstone are raw material for the manufacture of mortar, soil conditioner.