Know all about Picrite and Oil shale properties here. All properties of rocks are important as they define the type of rock and its application. Picrite belongs to Igneous Rocks while Oil shale belongs to Sedimentary Rocks.Texture of Picrite is Earthy, Rough whereas that of Oil shale is Splintery. Picrite appears Rough and Shiny and Oil shale appears Muddy. The luster of Picrite is subvitreous to dull while that of Oil shale is dull. Picrite is available in black, brown, colourless, green, grey, pink, white, yellow colors whereas Oil shale is available in black, brown, buff, green, grey, red, yellow colors. The commercial uses of Picrite are as a feed additive for livestock, as armour rock for sea walls, metallurgical flux, pottery, source of magnesia (mgo) and that of Oil shale are an oil and gas reservoir.