1. Shale: Shale is a fine-grained sedimentary rock formed from the compaction and cementation of clay, silt, and other fine particles. It often contains varying amounts of quartz and feldspar, which contribute to its hardness and durability.
2. Mudstone: Mudstone is another sedimentary rock similar to shale, but it lacks the fissile nature (the ability to split into layers) that characterizes shale. It's also primarily composed of clay minerals, with varying amounts of quartz and feldspar.
It's important to note that the exact mineral composition of these rocks can vary depending on the source of the sediment and the conditions of their formation.
