Argil and Terra cotta

Argil noun - A white clay (especially a white clay used by potters).

Terra cotta and argil are semantically related in workable earth material topic. In some cases you can use "Terra cotta" instead a noun "Argil", when it comes to topics like baked earth.

Terra cotta noun - A hard unglazed brownish-red earthenware.

Argil and terra cotta are semantically related in workable earth material topic. You can use "Argil" instead a noun phrase "Terra cotta", if it concerns topics such as baked earth.