Density may differ appreciably between distinct rock varieties as a result of variations in mineralogy and porosity. Familiarity with the distribution of underground rock densities can support in interpreting subsurface geologic composition and rock variety. gneiss Gneiss displays a nicely-created foliation as well as a badly produced schistosity and cleavage. https://sticksofrock25677.blogripley.com/37145539/considerations-to-know-about-sticks-of-rock