Know all about Icelandite and Gneiss properties here. All properties of rocks are important as they define the type of rock and its application. Icelandite belongs to Igneous Rocks while Gneiss belongs to Metamorphic Rocks.Texture of Icelandite is Aphanitic to Porphyritic whereas that of Gneiss is Banded, Foliated, Platy. Icelandite appears Dull and Soft and Gneiss appears Foliated. The luster of Icelandite is vitreous while that of Gneiss is dull. Icelandite is available in bluish - grey, grey, pink, yellow colors whereas Gneiss is available in black, brown, pink, red, white colors. The commercial uses of Icelandite are cemetery markers, creating artwork and that of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums.