Argillite and Soapstone

Argillite noun - A sedimentary rock differing from shale in being bound by silica and from slate in having no slate cleavages.

Soapstone and argillite are semantically related. In some cases you can use "Soapstone" instead a noun "Argillite".

Soapstone noun - A soft heavy compact variety of talc having a soapy feel; used to make hearths and tabletops and ornaments.

Argillite and soapstone are semantically related. You can use "Argillite" instead a noun "Soapstone".