Resin in mine, evidently low, eventually at first rising (5)
I believe the answer is:
elemi
'resin' is the definition.
(elemi is a kind of resin)
'in mine evidently low eventually at first rising' is the wordplay.
'at first' indicates taking the first letters.
'rising' says the letters should be written backwards (going up in a down clue).
The initial letters of 'in mine evidently low eventually' is 'imele'.
'imele' backwards is 'ELEMI'.
(Other definitions for elemi that I've seen before include "Fragrant tree resin used as incense - I'm Lee (anag)" , "Fragrant resin used as incense - Emile (anag)" , "aromatic resin" , "Fragrant substance" , "Extract" .)