Which of these is not a type of soil?

Clay is a type of fine-grained natural soil material containing clay minerals. It develops plasticity when wet, due to a molecular film of water surrounding the clay particles, but becomes hard, brittle and non–plastic upon drying.

Slit soil is made up of minerals (mainly quartz) and tiny pieces of organic material. It is very fertile.

Sand or sandy soil is formed by the smallest or fine particles of weathering rocks. This soil is known as the poorest type of soil for agriculture and growing plants as they have very low nutritional value and poor water-holding capacity.

Green soil is not a type of soil.