Know all about Tachylite and Rhyodacite properties here. All properties of rocks are important as they define the type of rock and its application. Tachylite and Rhyodacite belong to Igneous Rocks.Texture of Tachylite is Vitreous whereas that of Rhyodacite is Earthy. Tachylite appears Glassy and Rhyodacite appears Skeletal. The luster of Tachylite is resinous while that of Rhyodacite is greasy to dull. Tachylite is available in black, dark brown colors whereas Rhyodacite is available in black to grey, dark greenish - grey colors. The commercial uses of Tachylite and Rhyodacite are cemetery markers, creating artwork.