Husband and I eat meat — fantastic source of iron (9)
I believe the answer is:
haematite
'source of iron' is the definition.
(I've seen this before)
'husband and i eat meat fantastic' is the wordplay.
'husband' becomes 'h' (abbreviation).
'and' means one lot of letters go next to another.
'fantastic' is an anagram indicator (a fantastic or improbable ordering of the letters).
'i'+'eat'+'meat'='ieatmeat'
'ieatmeat' with letters rearranged gives 'aematite'.
'h'+'aematite'='HAEMATITE'
(Other definitions for haematite that I've seen before include "source of iron" , "Iron ore" .)