It often occurs as rectangular crystals. Pyrite is mainly associated with acid sulfate soils. Hematite has a metallic luster with a color ranging from dark steel gray, dull red, to iron black. Large crystals of hematite are a main constituent of most laterites. Goethite is one of the primary pigmenting agents in soils usually occurring as small grains dispersed throughout the matrix or as grain coatings.
Identification is difficult because of the small crystal size.
Lithorelicts include pieces of sandstone, siltstone, shale, limestone, and fine-grained igneous or metamorphic rocks. These clastics are derived from an outside source and incorporated into the soil parent material. These clastics are derived from an outside source and incorporated into the soil parent material. Identification depends on recognition of structure and individual components, and consideration of possible sources. Shales and siltstones frequently show bedding and limestone may have fossils.