Know all about Icelandite and Tachylite properties here. All properties of rocks are important as they define the type of rock and its application. Icelandite and Tachylite belong to Igneous Rocks.Texture of Icelandite is Aphanitic to Porphyritic whereas that of Tachylite is Vitreous. Icelandite appears Dull and Soft and Tachylite appears Glassy. The luster of Icelandite is vitreous while that of Tachylite is resinous. Icelandite is available in bluish - grey, grey, pink, yellow colors whereas Tachylite is available in black, dark brown colors. The commercial uses of Icelandite and Tachylite are cemetery markers, creating artwork.