My first post is cri de coeur! I have a full grid minus one cell, the appropriate cipher and keyword but am stuck on the dreaded 16a!! My problem is the unchecked cell. I have seen the very kind hints 'homophone', 'nobles' (my guess these also sound like serious lung infection) and geological 'levels' but all I can make out of the letters I have, plus a guess at the seventh, is a thin silk fabric! Been doing the Listener for years but this clue has me floundering. Someone please help or another sleepless night beckons!
An excellent puzzle, by the way, and thank you to all the posters on here for many enjoyable expositions over the years.