Piece of skin torn by silver pin (6)
I believe the answer is:
agnail
'piece of skin' is the definition.
'agnail' can be an answer for 'skin' (agnail is a kind of skin). I am unsure of the 'piece of' bit.
'torn by silver pin' is the wordplay.
I cannot quite see how this works, but
'silver' could be 'ag' (Ag is the chemical symbol for silver) and 'ag' is found in the answer.
'pin' could be 'nail' (I've seen this before) and 'nail' is found within the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for agnail that I've seen before include "tear on index?" , "Torn skin" , "It may cause irritation to finger" .)