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 Conglomerate Uses. We have provided you with all information about Conglomerate rock here. Conglomerate is a sedimentary rock which forms from rounded gravel and boulder sized clasts which are cemented together in a matrix. Conglomerate is available in beige, black, brown, buff, light to dark grey, orange, rust, white, yellow colors. The streak of a rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Conglomerate is white. Get to know more about Conglomerate rock and characteristics of Conglomerate rock in the next sections.