Bauxite, for instance, has nothing about it! (3)
I believe the answer is:
ore
'bauxite' is the definition.
(I've seen this in another clue)
'instance has nothing about it' is the wordplay.
'instance has' becomes 'r' (I can't explain this - if you can you should give a lot more credence to this answer).
'nothing' becomes 'O' (looks like zero - 0).
'about' says the letters should be written in reverse.
'it' becomes 'e' ('e' can mean 'electronic' which is similar to 'IT').
'r'+'o'='ro'
'ro' in reverse letter order is 'or'.
'or'+'e'='ORE'
'for' is the link.
Can you help me to learn more?
(Other definitions for ore that I've seen before include "Mined material" , "It's mined for minerals" , "it could be gold" , "Unwrought iron" , "Mineral deposit" .)