You searched for: “geophagous
geophagous (adjective) (not comparable)
Regarding the consumption of soil; deriving nutrients from soil or the sediment: Geophagous ingestion pertains to eating earthy substances like clay which can be a result of starvation, lack of something in the diet, or possibly as a result of a mental illness.

A page about a pica eating More details about geophagy.