Rocks are naturally occurring solids which are composed of minerals & have been used by humans since ages. From Stone Age, rocks are used for various purposes. Also, the metals and minerals found in rock play an important role in our life. Get to know all the Appinite Uses. We have provided you with all information about Appinite rock here. Appinite is an igneous rock in which the crystals are so fine grained that individual minerals cannot be easily distinguished. Appinite is available in black, bluish - grey, brown, dark greenish - grey, green, grey colors. The streak of a rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Appinite is white. Get to know more about Appinite rock and characteristics of Appinite rock in the next sections.