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