Here's a little more about shale:

* Formation: Shale forms from layers of clay, silt, and other fine-grained sediments that are deposited in quiet water environments like lakes, swamps, or the deep ocean floor.

* Compression: Over time, the weight of overlying sediment compresses these layers, squeezing out water and hardening the clay into shale.

* Texture: Shale is characterized by its layered or fissile texture, meaning it breaks easily along parallel planes.

* Uses: Shale is used in various applications, including roofing tiles, brick, and as a source of oil and natural gas (shale oil and shale gas).