Material wealth (9)
This clue is a double definition.
'material' is the first definition.
(I know that material can be written as substance)
'wealth' is the second definition.
(I've seen this before)
(Other definitions for substance that I've seen before include "Subject matter" , "Property" , "Physical matter" , "Matter or material that a thing is made of" , "Basic matter" .)
'material wealth' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for mammon that I've seen before include "money" , "God of material wealth" , "Greed personified" , "Wealth personified, you cannot serve God an . . . . . ." , "Bible 'You cannot serve God and . . . . . .'" .)