Know all about Gossan and Tachylite properties here. All properties of rocks are important as they define the type of rock and its application. Gossan belongs to Metamorphic Rocks while Tachylite belongs to Igneous Rocks.Texture of Gossan is Rough, Sandy whereas that of Tachylite is Vitreous. Gossan appears Dull and Banded and Tachylite appears Glassy. The luster of Gossan is metallic while that of Tachylite is resinous. Gossan is available in brown, brown- black, gold, green, rust colors whereas Tachylite is available in black, dark brown colors. The commercial uses of Gossan are cemetery markers, commemorative tablets, gemstone and that of Tachylite are cemetery markers, creating artwork.