A projecting lug no longer made of clay (7)

I believe the answer is:

earthen

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'made of clay' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for earthen that I've seen before include "Made of baked clay, perhaps ware" , "Like many pots" , "from the ground" , "Made of baked or fired clay" , "(Of pot) made of baked clay" .)

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