Part of the Faculty of Social Sciences at the University of Victoria, PACTAC is a pioneering, multidisciplinary research centre, and home to the electronic scholarly journal CTheory, CTheory Archive, and CTheory Multimedia.
Rocks: Rocks are a composed of one or more minerals. A rock can be made up of only one mineral or, as shown in the figure, a rock can be made up of a number of different minerals. So, rocks are composed of one or more minerals and minerals are composed of one or more elements. Previous Item: Why should we study rocks? Go Up: Learn About Rocks
Sandstone (sometimes known as arenite) is a clastic sedimentary rock composed mainly of sand-sized minerals or rock grains. Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust.Like sand, sandstone may be any color, but the most common colors are: tan, brown, yellow, red, grey, pink, white, and black.hey are formed from cemented grains that may either be fragments of a pre-existing rock or be mono-minerallic crystals. The cements binding these grains together are typically calcite, clays, and silica. Grain sizes in sands are defined (in geology) within the range of 0.0625 mm to 2 mm (0.002â0.079 inches).