Know all about Oil shale and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Oil shale belongs to Sedimentary Rocks while Tephrite belongs to Igneous Rocks.Texture of Oil shale is Splintery whereas that of Tephrite is Aphanitic to Porphyritic. Oil shale appears Muddy and Tephrite appears Vesicular. The luster of Oil shale is dull while that of Tephrite is subvitreous to dull. Oil shale is available in black, brown, buff, green, grey, red, yellow colors whereas Tephrite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Oil shale are an oil and gas reservoir and that of Tephrite are production of lime, soil conditioner.