Know all about Chert and Nephelinite properties here. All properties of rocks are important as they define the type of rock and its application. Chert belongs to Sedimentary Rocks while Nephelinite belongs to Igneous Rocks.Texture of Chert is Banded, Rough whereas that of Nephelinite is Aphanitic. Chert appears Glassy or Pearly and Nephelinite appears Skeletal. The luster of Chert is waxy and dull while that of Nephelinite is vitreous to metallic. Chert is available in black, brown, green, grey, red, white colors whereas Nephelinite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms and that of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo).