fissility
Fissility refers to the tendency of a rock to split into thin, parallel layers or laminae along bedding planes--particularly fine-grained sedimentary rocks like shales. This property results from the alignment of clay minerals and other platy minerals within the rock fabric, which is often the result of compaction and diagenesis. Fissility can be influenced by factors such as the depositional environment, sediment composition, and burial history.
