Is mineral up in Orkney essentially close to miracle fuel? (8)

'fuel?' is the definition.
(kerosine is a kind of fuel)

'is mineral up in orkney essentially close to miracle' is the wordplay.
'mineral' becomes 'ore' (ore is a kind of mineral).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'in' means one lot of letters goes inside another.
'essentially' indicates the central letters.
'close to' says to take the final letters (the close/ending of).
The central letters of 'orkney' are 'kn'.
The last letter of 'miracle' is 'e'.
'is'+'ore'='isore'
'isore' written backwards gives 'erosi'.
'erosi' put within 'kn' is 'kerosin'.
'kerosin'+'e'='KEROSINE'