The transformation of the original material into a different one. Particle size is very important in the process of chemical weathering. The greater the surface area of a particle the more susceptible it is to chemical weathering. Sedimentary rocks have a wide range of colors that include red, brown, gray, yellow, pink, black, green and purple. The most important colors are the iron bearing compounds, brown, red, yellow and green.
Red rocks owe their colors to the fine hematite and green rocks to chlorite and lack iron oxide.
The three major types of sedimentary rocks are mud rocks, sandstones and carbonate rocks. The particles include clay to course silt. These particles are suspended in water and can settle and accumulate only in still waters such as lakes, deltas and lagoons. These accumulate in areas of high energy environments of moving fluids such as rivers and beaches. Sandstones consist of particles of very fine to very coarse grained sand.