Know all about Siltstone and Oil shale properties here. All properties of rocks are important as they define the type of rock and its application. Siltstone and Oil shale belong to Sedimentary Rocks.Texture of Siltstone is Clastic whereas that of Oil shale is Splintery. Siltstone appears Rough and Oil shale appears Muddy. The luster of Siltstone and Oil shale is dull. Siltstone is available in brown, red, reddish brown colors whereas Oil shale is available in black, brown, buff, green, grey, red, yellow colors. The commercial uses of Siltstone are raw material for the manufacture of mortar, soil conditioner and that of Oil shale are an oil and gas reservoir.