Melt ore, put mostly in order, for fuel source (9)

I believe the answer is:

petroleum

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'fuel source' is the definition.
'petroleum' can be an answer for 'source' (I have seen 'Source of fuel' mean 'petroleum' so perhaps 'source' could also mean 'petroleum'). I am not certain of the 'fuel' bit.

'melt ore put mostly in order' is the wordplay.
'mostly' means to remove the last letter.
'in order' is an anagram indicator (the letters in a new order).
'melt'+'ore'+'put'='meltoreput'
'meltoreput' with its last letter removed is 'meltorepu'.
'meltorepu' with letters rearranged gives 'PETROLEUM'.

'for' acts as a link.

Can you help me to learn more?

(Other definitions for petroleum that I've seen before include "Hydrocarbon oil" , "Fuel oil" , "Source of fuel" , "Oil well product" , "It helps in getting things moving" .)

I've seen this clue in The Telegraph.

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