Properties of Chalk and Siltstone play an important role in determining the type of rock. Along with Chalk vs Siltstone properties, get to know more about Chalk Definition and Siltstone Definition. For the ease of understanding, the properties of rocks are divided into physical and thermal properties. Rocks have a variety of properties like hardness, color, specific gravity, fracture, cleavage, luster etc. Know all about physical and thermal properties of Chalk and Siltstone.